Trabsact Sagme Diaries

CROSS

2011-12-05T15:46:00.000Z

12* moves & group restriction

Y play; the goal is to make a group connecting 3 non-adjacent sides.

The winner is whoever makes a Y;
or if no-one does, the player who first made a cross loses.

Game Sample
    ___xx_____oo___
 1:  -- i6   k4 k6
 2:  l5 l7   j5 k8
 3:  j7 o6   g6 n7
 4:  f7 m6   h5 g8
 5:  n3 i8   m4 p5
 6:  o4 f7   n5 d7
 7:  f9 h7   e6 s6
 8:  k2 h9   h3 r5
 9:  h1 r7   j1 m2
10:  t7 i2   l3 p7
11:  u6 c8   q6 d9
12:  q8 n9   l9 p9
13:  m8 q10  o8 p11
14:  r9 e8   o10 a6
15:  resign
    
: abcdefghijklmnopqrstu  
:      . x o . . .        1
:     . . x x o . .       2
:    . . o . o x . .      3
:   . . . . o o x . .     4
:  . . x o o x o o o .    5
: O . o o x o x x o o x   6
:  . o x x x x o o x x    7
:   x x o x o x o x .     8
:    o x x . o x o x      9
:     . . . . . O x      10
:      . . . . . o       11
: abcdefghijklmnopqrstu

ONE-HIT PROGRESSIVE CHESS

2011-07-27T20:00:00.000+01:00

As FIDE Progressive Chess except:

Each player makes from 1 to the turn number, of moves, subject to
the condition that any capture, check or promotion ends the series.

Sample Game



     1. e4
     2. e6 Be7
     3. Qg4 Qg5 Q:e7+
     4. N:e7
     5. e4 Nf3e5c6:d8
     6. f5f4 O-O d6 Nc6:d8
     7. Bb5 Bd7 a4 b3 c4 f3 B:c8
     8. Na6b4 a5 c5 g5 h5h4 R:c8
     9. g4 h3 d5 Rh2 Rc3 Raa2 Bd2 B:b4
    10. b6 e5 Kf7 Rc7 Re8e7 c:b4
    11. c5 Rc4 Rac2 Kd3 c:b6
    12. Rb7 Rec7c5 Ke7 Ne6d4e2g1:h3
    13. N....h3
    14. Rb8 K..b7 Rbc8 R:c4
    15. K..b2 Rc1 b:c4
    16. K:b6
    17. Nf2 R...h3 Kb3 N...e7 N:c8+
    18. K..:c8
    19. c567 K...c6 R...b8++
    
Final Position:

 . . k . . . . .
 . . O . . . . .
 . . K p . . . .
 p . . O p . p .
 O p . . O p O p
 . . . . . O . R
 . . . . . . . .
 . . . . . . . .

CADUCEUS

2011-07-11T12:27:00.000+01:00

Played on an 8x8 board, each player starts with two stones, at opposite corners.
Group-restricted 12* moves per turn.

For each move, a player removes the tail of one of his groups, then adds two successive rookwise-adjacent new stones on empty cells at the head of it.

A player loses if he cannot complete a legal turn.


The first moves (the '-' clarifies the chain structure):

                       _J___N_    _B___T_
 . . . . . . . .    1. es   --    ee   ss
 . j-j . . . . ,    2. es   nw    nn   ww
 . . J . . T-t-t    3.
 . . . . . . . .    4.
 . . . . . . . .    5.
 . . B . . . . .    6.
 . . b . . . N-n    7.
 . , b . . . . .    8.

and the entire game:
                       _J__N_    _B__T_
 . . t-t-t-t-t-t    1. es  --    ee  ss
 . . t . . ,-t-t    2. es  nw    nn  ww
 . T-t . . . . n    3. se  wn    en  ww
 . N-n-n-n-n . n    4. es  nn    ww  ne
 b-b-b . . n-n-n    5. ss  en    ss  ee
 b . B . . J-j-j    6. ws  es    es  en
 b b-b j-j . . j    7. ee  sw    ww  ww
 b-b-b j-j-j-j-j    8. ee  wn    nn  ww
                   9. nn  ww    ne  ws
                   10. ww  ww    es  sw
                   11. resign

A better variant uses double removal and triple growth for faster moves (and a 10x10 board)

A game example:

                      
     _J____N_   _B____T_
 1.  wws  ---   sss  nww
 2.  ssw  enn   eee  wnn
 3.  wss  nee   sse  nne
 4.  sss  sww   nnn  sss
 5.  eee  nnn   www  een
 6.  sww  wne   nee  wnn
 7.  wwn  ees   ees  www
 8.  www  ese   ene  nee
 9.  wnn  sww   see  ees
10.  nnn  see   nnw  sss
11.  nnn  ees   www  swn
12.  ese  swn   wss  nww
13.  ess  wsw   ssw  nee
14.  wss  nws   ses  nnw
15.  sww  wnw   enn  nee
16.  nen  swn   nen  sss
17.  wne  nee   wne  sss
18.  nwn  eee   nes  swn
19.  nws  ees   resign

Final Board:
 j-j . . b-. b-b . B  1
 j J j-j b b-b-b-b-b  2
 j-j . j b b-b t-t-t  3
 j-j j-j b b-b t-t t  4
 j-j j b-b b . . t t  5
 j-j j b-b b t-t-t t  6
 j-j-j . b-b t T-t t  7
 n-n-n-n-n-n-n-n t t  8
 n n-n n-n n-. N t t  9
 n-n n-n n-n . . t-t 10

This game was inspired by the light motorcyles from the TRON movies.

On Natural & Artificial Games

2011-06-06T13:53:00.000+01:00

Can we use the terms natural/artificial for games, in general?

One way to look at this is to relate naturalness to simplicity. Simple games like Hex, Tic Tac Toe or, perhaps, Go, seem almost like discoveries, rather than inventions. But the fact that Hex was only "discovered" in the 1940s does give us pause to ponder. Simplicity is culturally dependent, just as are more obvious or trivial things - e.g. the positional numerical system, or the moral statement "slavery is wrong" -- which were not so in the past.

Another way to look at this is using History. Games, or game concepts, that seem to be invented independently are, at least, cognitively attractive to humans. Perhaps they are cognitively attractive to conscious beings in general, and so, they may even exist in alien cultures. Some examples of those are race games, or Tic Tac Toe/Gomoku variants. Possibly, seed games, Mancalas, also belong here. So, a natural game would be an instance of one of these archetypal game concepts. Of course, as usual, the frontier is blurred. Bao is a very complicated Mancala game. Overly baroque variants can hardly be seen as natural. Shall we include Checkers/Alquerque or Chess games? And how many add-ons can a game include and still be considered a natural one?

A third way to try to make sense of this separation between natural and artificial, is to look into the game's history.

Games like Chess, Go, Mancala and Checkers have evolved through centuries, absorbing gaming experience into their progressive adaptable rules. As in biological natural selection, these games are more like species, with their life trees,
their historical compromises, their multiple branches (cultural instead of biological). So, in this case, every game started in one or more human minds, in some raw artificial state, and was tested in a social environment. Like most species, most games must have become extinct quite quickly. But a few were able to adapt to the cultural intricacies of the memetic landscape of its inventors. And then, when society changed, games also changed, like any adaptable, flexible population of organisms. Of course, the analogy only goes so far. Unlike fossils, if they are rediscovered, games can be brought back and enjoy a new life eventually under new clothes. (The Game of Ur, and Senet, with their reconstructed rules, are famous examples).

Just as for the concept of species, we might differ our final judgement about our recent games. Perhaps Hex will have a biography (it already has thriving children, like Y). Game inventors, nowadays, have an immense set of game ideas and, like alchemists, they try to mix them, mould them into new games. Most of those, as in the past, will become extinct and never get beyond being artificial concepts. Others, because they say something to generations of players, will be carried along with our evolving society and will start to have a biography. They will, slowly and in unexpected ways, become natural concepts.

[also posted in rec.games.combinatorial]

Two Games for Three Players

2011-06-01T17:38:00.000+01:00

Here are a couple of games to be played with three players:

Triad by Cameron Browne

Rules can be checked here.

An older game is Atride by Gauthier Fourcade:

Board Games Studies 2011

2011-05-27T16:54:00.000+01:00

This year edition of BGS happened in Brugge, Belgium. The meeting was held at the KHBO-Spellenarchief. The game archive has several thousand board games and has a database (in Dutch) which is being slowly uploaded with game information and, hopefully, game rules. Here are some pictures from their public section:

And here is a panoramic view (as usual, click to enlarge):

Lots of thousands of games were donated by the Dutch game collector and inventor, Fred Horn, who still collaborates with the Museum. Here is a picture of him (the middle guy, talking math & games with Jorge Nuno and Carlos Santos, two Portuguese friends):

Irving Finkel presented "On to Square Two – the question of dissemination" talking about how games travel between cultures. This travel is useful for game survival but has also the problem of game contamination. Some games may even replace and destroy old games. For a game Historian the modern waves of European migration (like colonists or missionaries) to the rest of the world meant terrible news.

In the colloquium a participant (I don't recall his name...) presented a rediscovered picture from an old book, picturing Adam & Eve in the garden of Eden. Some say they are playing a board game (I saw just them picking and eating grapes or something like that...). Anyway, the picture is pretty:

Michel Boutin made a nice presentation called "The structure of games" were he made an historical perspective of how games were classified in the past.

Fehde

2011-05-22T10:08:00.000+01:00

Anyone knows Dutch?

Transvaal

2011-05-21T08:44:00.000+01:00

A Bavarian game from early 20th century (click to enlarge):

Chivalry

2011-05-20T09:30:00.004+01:00

A 1887 game from George Parker (click to enlarge):

Playing Go

2010-12-01T18:03:00.003Z

This is a photo from a Chinese restaurant near Lisbon where I sometimes eat:

and also a detail of the actual game:

CHICKEN HEXY

2010-11-30T08:38:00.000Z

8 hex-hex board initially empty.
Players may drop only isolated non-edge X's in the preliminary phase; 1, 2 or 3 at his own choice.
On any turn, either player may take X and pass.
Normal alternation follows, and X wins by connecting three non-adjacent sides.
If X fails, O wins.

Sample Game:



0: h2 g5 c7, g7, j4 j6, 2nd player takes

: abcdefghijklmnopqrstuvwxy       _OO___XX_
|       . . . . . . .         1.   r8   p10
|      . x . . . . . .        2.   l8   k9
|     . . . . . . . . .       3.   n10  j11
|    . . . x . . o . . .      4.   n12  l12
|   . . x . . . . . . . .     5.   p4   p6
|  . . . . x . o x . . . .    6.   n6   m7
| . x . x . . x o . . . . .   7.   o7   p8
|  . . . . . o x . o 4 . .    8.   u11  t10
|   . . . x . . . . 2 3 .     9.   OO resigns
|    . . . . o x . x 1 .     10.
|     . . x . . . . o .      11.
|      . . x o . . . .       12.
|       . . . . . . .        13.
abcdefghijklmnopqrstuvwxy

GO-6-MOKU

2010-06-08T07:14:00.000+01:00

Rules of 9x9 Go, except that there is no passing and the winner is
whoever gets a 6-in-a-row. Suicide is illegal, except that a 6-row
may be completed in an otherwise liberty-less position. No swap.
Neither dagger move may be used to capture, nor to make a winning
6-line, and they must finish in different groups.

Sample Game:



   _XX____OO_   O has dagger
 1. e5    d4
 2. d5    c5
 3. c6    b6
 4. e3    e4 
 5. f4    c4
 6. g5    h5
 7. c7    g3
 8. h6    d2
 9. h4   e2,f3  X has dagger
10. i5:  resign

a b c d e f g h i
. . . . . . . . . 1 
. . . o o . . . . 2 
. . . . x o o . . 3 
. . o o o x . x . 4 
. . o x x . x : X 5 
. o x . . . . x . 6 
. . x . . . . . . 7 
. . . . . . . . . 8
. . . . . . . . . 9

TROMAZONS

2010-06-03T06:59:00.000+01:00

On a 8x8, each one starts with 4 stones. A move consists of moving one piece along to a rookwise adjacent empty cell, then placing a wall adjacent to it. 12* moves. A player unable to complete a move loses.

Initial Position


:     a   b   c   d   e   f   g   h
|   +-------------------------------+
| 8 |         B           J         |
|   |   +   +   +   +   +   +   +   |
| 7 |                               |
|   |   +   +   +   +   +   +   +   |
| 6 | J                           B |
|   |   +   +   +   +   +   +   +   |
| 5 |                               |
|   |   +   +   +   +   +   +   +   |
| 4 |                               |
|   |   +   +   +   +   +   +   +   |
| 3 | B                           J |
|   |   +   +   +   +   +   +   +   |
| 2 |                               |
|   |   +   +   +   +   +   +   +   |
| 1 |         J           B         |
|   +-------------------------------+
:     a   b   c   d   e   f   g   h

Sample Game:



       B            J
    =====================   
1.  ---  b3S     c2W  g3S
2.  c3S  e1W     f7N  f3S
3.  h5N  e2N     d2E  e3E 
4.  d3E  g5N     e4S  f6N
5.  f5N  f2S     e6E  b6W
6.  d4E  f4W     d3N  d6S
7.  f5S  c4N     c3N  e5S
8.  b4S  c7S     d7W  b3E
9.  c8E  a4E     a3N  b5W
10. resign

:     a   b   c   d   e   f   g   h
|   +-------------------------------+
| 8 |         B |                   | 
|   |   +   +   +   +   +---+   +   |  
| 7 |           | J                 |
|   |   +   +---+   +   +---+   +   |
| 6 |   |               |           |
|   |   +   +   +---+   +---+---+---|
| 5 |   | J           J   B         | 
|   |   +   +---+   +---+---+   +   |
| 4 | B |           |   |           | 
|   |---+---+---+---+---+   +   +   |
| 3 | J     |       |   |           |
|   |   +---+---+   +---+---+---+   |
| 2 |       |       |     B         |
|   |   +   +   +   +   +---+   +   |
| 1 |               |               |
|   +-------------------------------+
:     a   b   c   d   e   f   g   h

SESQUY

2010-06-01T09:19:00.000+01:00

On each turn, each player drops a friendly stone on an empty cell and then
(optionally) moves another friendly stone to an adjacent empty cell.

Sample game:


                                  XX            OO (swapped)
: abcdefghijklmnopqrstuvwxy  ================================
|             .              1. l6   ----       m11  ----
|            . .             2. j10  l6 m7      k9   m11 l10 
|           . . .            3. j8   j10 i9     h10  k9  j10   
|          . . . .           4. o9   j8 l8      o11  l10 m11
|         . . . . .          5. r10  l8 m9      r12  j10 k11
|        . . . x . .         6. u11  i9 j10     t12  h10 i11
|       . . . . . . x        7. v12  o9 p10     t10  t12 s11
|      . . . . . o O o       8. p12  r10 q11    o9   o11 n10
|     . . . . x o . x ,      9. s9   p10r10     p8   t10 u9
|    . . . x . o . x . .    10. s7   m7n6       r8   u9  t8
|   . . . o o o . x o x .   11. X resigns
|  . . . . . . . x o . x .  12. 
| . . . . . . . . . . . . . 13. 
: abcdefghijklmnopqrstuvwxy 14.

OCTATOL

2010-05-18T21:09:00.000+01:00

Move sequence 36* with group restriction
(i.e., no two stones dropped in the same group/turn)

TO WIN: join 2 opposite groups, OR make a Y that prevents this.

Initial setup:



|   abcdefghijklmnopqrstuvwxyzABC
|            X X X O O O         
|         O . . . . . . . X          1
|        O . . . . . . . . X         2
|       O . . . . . . . . . X        3
|      X . . . . . . . . .   O       4
|     X . . . . . . . . . . . O      5
|    X . . . . . . . . . . . . O     6
|   . . . . . . . . . . . . . . .    7
|  O . . . . . . . . . . . . . . X   8
| O . . . . . . . . . . . .   . . X  9
|  O . . . . . . . . . . . . . . X  10
|   . . . . . . . . . . . . . . .   11
|  X . . . . . . . . . . . . . . O  12
| X . . . . . . . . . . . . . . . O 13
|  X . . . . . . . . . . . . . . O  14
|   . . . . . . . . . . . . . . .   15
|    O . . . . . . . . . . . . X    16
|     O . . . . . . . . . . . X     17
|      O . . . . . . . . . . X      18
|       X . . . . . . . . . O       19
|        X . . . . . . . . O        20
|         X . . . . . . . O         21
|            O O O X X X           
|   abcdefghijklmnopqrstuvwxyzABC

Game sample:



|   abcdefghijklmnopqrstuvwxyzABC        OO starts
|            X X X O O O                 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
|         O x . . . o . . X          1.  ..   ..   ..   o9   l12  r12
|        O . . . . . . . . X         2.  j10  t10  m11  q11  o13  o15
|       O . x . . . o . . . X        3.  o7   p10  s11  r14  n12  i13
|      X . . . . . o . . .   O       4.  u9   j12  p12  s13  j14  n16
|     X . x . . . o . . . . . O      5.  o5   r10  k13  n14  f12  f14
|    X . . . o . . . . . . . . O     6.  f8   n8   o11  l14  q15  t16
|   . x . . . . o o . . . . . . .    7.  j8   g9   p8   g13  p14  u15
|  O . x x x o . x o . . . . . . X   8.  h8   f10  c11  i11  q13  s15
| O . o x o o . o o . . x .   . . X  9.  j6   i9   g11  l10  l16  t14
|  O . x x o x o . o o x . . . . X  10.  d10  k11  d14  g15  m15  w17
|   x x . o x x x x x o . . . . .   11.  m7   h10  w13  f16  i15  i17
|  X . x o . x o o x o . . . . . O  12.  d8   a11  e15  g17  m17  l20
| X . o o o o o o x x x . o . . . O 13.  q3   m9   h14  i19  i21  k17
|  X x x o o x x o o o o . . . . O  14.  k15  h16  j18  x18  m19  h20
|   . o x x o x x x x x o . . . .   15.  m13  f18  j20  l18  u17  u19
|    O . o x x o x . . x o . . X    16.  c7   d12  j16  q17  t18  q19
|     O . x o o x . x * o x . X     17.  c9   c13  c15  n18  r18  v16
|      O o o x o o x o x x x X      18.  e9   p18  v18  k19  v20  s21
|       X . o x x . x o o x O       19.  q1   p4   h18  p20  s19  u21
|        X x o x . o x * x O        20.  i1   i3   g5   c14  w19  r20
|         X o . . . . x o O         21.  OO resigns (x forces at one of the *s)
|            O O O X X X           
|   abcdefghijklmnopqrstuvwxyzABC

This game is based on Atoll, a game from Mark Steere

The Siege of Paris

2010-05-11T10:00:00.001+01:00

At 1870 Paris was sieged by Prussian forces and, in four months, took over the city and won one of the n wars between France and Germany. In the UK it inspired the creation of a game called appropriately "The Siege of Paris" (the game appeared also at 1870). Here's an original box (available at the Oxford Digital Library):

Here the initial setup:
and a better view of the board (from BoardGameGeek):
Also, at Oxford Digital Library, here the scan of the original rules (click to zoom):

At BoardGameGeek there's also the rules in text format:

The Siege of Paris

This interesting and amusing game of skill can be played by two, three or five persons; one takes the Garrison or Fort, the others the outside lines.

The positions of the Men are as follows :- The General on the right, the Colonel on the left, the Captains next,and the Lieutenants in the centre ; the placing of the Men in the Garrison is optional.

RULES OF THE GAME
1.-The Besieging party have 36 Men,viz., two Generals two Colonels, four Captains, four Lieutenants. to be equally divided, and to be in two colors, half to move on the Black Squares, and half on the White.
2.-The Besiegers cannot move backwards, Officers or Men.

THE MOVES OF THE BESIEGING PARTY
3.-The Generals move on White or Black Squares-one, two or three Squares at a time. straight, sideways and diagonally.
4.-The Colonel moves on White and Black Squares-one or two squares at a time, straight or sideways.
5.-The Captain moves on White or Black Squares-one square at a time, straight or sideways.
6.-The Lieutenants move diagonally-one or two Squares at a time.
7.-The Men move only diagonally whichever Square they are placed on.
8.-The Besieging party win the game by placing one Officer and three Men in the Garrison, and cannot be taken when inside.

RULES FOR THE GARRISON MEN
9.-The Garrison is occupied by eight Men, viz., one General, one Colonel and six Men, and win the game by taking 24 Men and six Officers.
10.-The Officers and Men of the Garrison cannot be taken, but the Men can be blocked in by the Besieging party, until they are relieved by their Officers.
11.-You are not compelled to take any Man; when any of the Besieging party are taken they must be unsupported, and place your man on the same Square.
12.-The Officers and Men of the Garrison to be Red.

MOVES OF THE GARRISON MEN
13.-The General can move any way-backwards or forwards, straight, sideways or diagonally, and take the same way one or two Squares at a time, either on Black orWhite Squares;
the Colonel moves on Black or White Squares, backwards or forwards, either sideways or straight, and takes the same way;
the Men move diagonally only, three on the white Squares and three on the Black, either backwards or forwards when outside the Garrison

Entered at Stationers' Hall

R.C.Bell provided a patch for solving some problems with the original rules (from BoardGameGeek):

Necessary additional rules and definitions for Siege of Paris. V1.0 May 2009

Win conditions
Garrison player: Capture 6 Besieging Officers and all Besieging Men.
Besieging Player: Having 1 Officer and 3 Men inside the Garrison. (Besieging pieces can not be taken once inside the Garrison.)
Or by blocking with Besieging pieces all legal moves by the Garrison forces. (Supported Besieging pieces can not be captured.)
Alternative win condition for Besieging Player: 1 Officer and 2 Men inside the Garrison.

Draw condition
When less than the pieces required for the chosen win condition remain on the board, then if 1 Besieging piece, or more, are inside the Garrison the game is a draw.

Starting position of Garrison pieces: These pieces may be arranged on the nodes inside the Garrison however the Garrison player wishes.

Turn order: Garrison, White, Garrison, Black, Garrison, White, ...

Alternative forced taking rule: The Besieging player can, if such a move is legal, command the Garrison player to take a Besieging piece.

Fort Gate: Entry to the fort is from the 2 squares (1 black square and 1 white) adjacent to the gates on each side of the fort.

Support: Besieging piece "A" is "supported" when another Besieging piece could legally move onto the square occupied by "A" but for the presence of "A". (Supported Besieging pieces can not be captured.)

Capture: As in chess, by moving the capturing Garrison piece onto the square occupied by the Besieging piece. (Garrison pieces can not be captured.)

---

More information at Jeux Strategie.

Hard Lines

2010-05-10T14:21:00.002+01:00

Here is an abstract game from c.1861 (more information at GARD). A kind of pattern game with captures and (re)drops. Check the board and the rules:

Three old Knight games

2010-05-06T10:14:00.005+01:00

At Michel Boutin presentation in the BGS, he mentioned a lot of 19th century board games that were patented in France, UK, Germany and in the US (and most already forgotten). Here are three related games using the Chess Knight, grouped together in a package called Rampant Knights.

These are the board (click to augment)

I found the rules at a Hoyle games edition. Here are the relevant pages:

He also mentioned a board game called "Jeu du Congo" (Game of the Congo) with a hexagonal board:

which was re-edited by Moulin in the French book Jeux de pions d’aujourd'hui. The rules can be found at issue 8 (Winter 2001) of the Abstract Games Magazine.

The Game

2010-05-05T19:09:00.003+01:00

Fred Horn showed me a picture of an old 1970/80's abstract game called "The Game"

He mentioned the rules orally, as he remembered:

The board starts empty and each piece (each player has five) enters in the player's corner.

On each turn, each player enters a piece off board or moves one friendly piece.

A piece moves [up to?] five cells in orthogonal directions with, at most, two changes of direction [no jumps allowed, it seems].

One piece may land in top of another. The pieces not in the top of a stack become blocked.

A stack can have, at most, three pieces. When a stack of size three is made, the piece in minority is captured.

When all the player's five pieces are on the board, the player cannot stop a friendly piece in his own corner (but it can move the piece thru it during the move sequence).

Wins the player that moves one of his pieces to the enemy's corner.

Any extra information about this game is appreciated.

Games @ BGS 2010

2010-05-05T11:43:00.004+01:00

In the Board Games Colloquium (BGS) it is always easy to find new abstract boards and ideas about games. Let me give a sample of this year, in Paris:

Herein you can see a game from Fred Horn, which basically can be seen as a Mancala kit.

These squares can be placed in any order the players like and every mancala board can be built this way. Of course, this game material can be used into many other types of games.

Here you can see Fred Horn (in the left) playing Fianco, another of his games:

A very interesting game is Nonaga, a 2008 invention by Víktor Bautista i Roca:

Visually, this reminds Zèrtz, but in this case, we have a pattern game and the board only changes shape (it does not decrease in size as in Zèrtz).

More info in Manqala.org, Juegos de Ingenio, Pseudolog.

Ancient Board Games @ The Louvre

2010-05-01T17:07:00.004+01:00

Here are some nice examples of race games from Ancient Egypt:
This was the text related to this game:
The obscure Mehen:
And the more known Senet (at least the text said it was Senet, it seems a version, half-way to the game of Ur):

And finally some old, old dice:

(photos taken in April 2010)

MOKU-GO

2010-04-27T07:26:00.000+01:00

Play and capture as at Go. Passing is forbidden.
The winner is whoever makes a 5-in-a-row.

Sample Game:
abcdefghijklmnopq       _xx___oo_
    . . . . .       1:   e3   h4
   . . . . . .      2:   c5   g5
  . x . O . . .     3:   e7   d4  
 . o . o o x . .    4:   d6   f8  
. x . o o o x . .   5:   g7   h8  
 . x . . x . . .    6:   i7   k7  
  . x x x o . .     7:   j8   i5
   . o o x . .      8:   j6   j4       
    . . . . .       9:   l4   k5
abcdefghijklmnopq  10:   m5   i3 & xx resigns

Aweet

2010-04-23T13:10:00.004+01:00

Aweet: Sudan's mancala (via Viktor Roca, via BBC)

Searching

2010-02-25T17:09:00.003Z

Anybody have this little book from the 1970s? I found that Frank Tapson also wrote two other books about abstract games:

Take two!: 32 board games for 2 players (1977)
Pick a pair!: 30 board games for 2 players (1980)

Any information about games in these books would be appreciated!

Penguins

2010-02-10T14:03:00.002Z

This is an adaptation of a 2003 commercial game called "Hey! That's My Fish!" designed by Alvydas Jakeliunas and Günter Cornett (*). This new rule set simplifies the game and makes it more interesting.

Rules: 12* move series on a hex-hex board of size 6. The first 3 moves on each side are to place a penguin on an empty cell. After that, the penguins move queenwise, and are not allowed to land on or pass over any other penguin or blank cell. The two moves in a series must be with different penguins. When a penguin moves it leaves the cell behind blank (eaten). If a player cannot complete a legal move, his opponent wins.

Game Sample:

      ooo       xxx
 1.  --  l7    j5  o4     
 2.  m2  h5    f7  o4m6
 3.  k4  i4    r5  n7
 4.  m8  l3    p3  c4
 5.  o6  e4    n1  p9
 6.  q6  l9    d5  n11 
 7.  j7  l11   m10 e6
 8.  p1  lk10  q10 h1
 9.  u6  kg6   t7  f3
10.  s6  c8    r7  i8
11.  RESIGN

Final Position:

:   abcdefghijklmnopqrstu   
:        .   . .           1
:       . . . .   . .      2
:      . x . .   .   .     3
:       o .     .   . .    4
:    .   .     . . .   .   5
:   . .   o . .       o    6
:    . .   .       . x     7
:       . . x .   . . .    8
:      . . . .   .   .     9
:       . . .     .       10
:        . . .     .      11
:   abcdefghijklmnopqrstu

(*) the original rules are: There is a hex board where each cell (fish) valuse 1, 2 or 3 points. Then (1) initially, take turns placing your penguins on tiles with a single fish. (2) move a penguin in a straight line of tiles and pick up the tile you just vacated, (3) if a penguin cannot move, remove it. Check Boardgeek for more information

12* TRICOLEUR HEXXAGON

2010-01-04T13:02:00.000Z

Like Hexxagon, except there are 3 colors (a,b,c) which capture each other (a takes b, b takes c, c takes a).

Win by annihilating opponent; or having most pieces in a blocked position.
Players must leave opponent with a non-pass move, if possible.

 Sample Game

| abcdefghijklmnopqrstuvwxy   
|       A . . . . . c        1
|      . . . . . . . .       2
|     . . . . B . . . .      3
|    . . . . . . . . . .     4
|   . . c . . . . . a . .    5
|  . . . . . . . . . . . .   6
| b . . . . . . . . . . . B  7
|  . . . . . . . . . . . .   8
|   . . A . . . . . C . .    9
|    . . . . . . . . . .    10
|     . . . . b . . . .     11
|      . . . . . . . .      12
|       C . . . . . a       13
| abcdefghijklmnopqrstuvwxy 


    ___ABC___      _____abc____ 
01. ....   e9      r4     o11
02. e9b8   m3j4    o11q9  g5e7 
03. j4g5   g9i11   c7     p4
04. k11    g5d6    q9o7   t6 
05. n10    g1i3    t6w7   s9s7
06. n10n8  i13     s5q7   Bs6 
07. m8r8   i13m13  w7t8   Br6 
08. n10    m13q13  q1     s9
09. n10r10 s13s11  q1n2   t8t10
10. u11    m11o9   Bq5    Ao2
11. q9     v10     t6w7   Cm3 
12. i3e4   As9     w7u9   An6
13. s9w9   r10     Cl4    Al6
14. x8     o9m7    An6    q5m5
15. u9s7   f6      o5q7   n6k7
16. j10   p8       j7g7  Bn4        
17. f4h6  d6f4     e7g5  l4n6       
18. c7e9  s11s9    Ah6   Co7        
19. Bf10  s9q7     n6p8  Ai7        
20. j10h8 e9h10    Ag7   q9s11      
21. g13g11 h10l10  Cr12  t10v8      
22. Be11  l10p10   s11u9 r4r6       
23. t10   q11      r6r8  Bl6        
24. Ch10  Aj10     As9   Bj6        
25. Cg9   p10n8    As11  s9o9       
26. j10m9 g9i7     j6f6  Ao9        
27: i7i5 f10f8     Ao11 Bg7    
28: d10  g11j12    h6h4 o11l10
29: Ck11 Ag11      l6n8 r10u11
30: Aj10 l10p10    n8q9 g7i9
31: j10n10 Aj10    s11o11 An8
32: i9g7   p12     q9s11 f4h6
33: k11m9  Ak11    q11o9 Bq11
34: j10n10 k11n12  t10p10 v8s9
35: p12t12 Ao11    w9u11 s9q8 
36: Bf10   Ao11    t12p12 Ag7 
37: j12f12 f10j10  g7i9  Cn10 
38: f12h10 e11h12  Cl10  n10j10
39. resign

Final Position

| abcdefghijklmnopqrstuvwxy   
|       . . . . . . c        1
|      . . . . c . . .       2
|     . . . . c . . . .      3
|    . . b . . b a . . .     4
|   . . b b . b . . . . .    5
|  . . . a . . . . . . . .   6
| . . . . . . . . . . . . .  7
|  . . . . . . c c . a . c   8
|   . . . : . c c . . a .    9
|    B . : c c . . . . a    10
|     . A c . . c c c c     11
|      . B . . c c c .      12
|       . . . . . . .       13
| abcdefghijklmnopqrstuvwxy 14

SQUARUBORUS

2009-12-22T13:10:00.001Z

[variant of Ouruborus] Players take turns moving both ends of the slime-worm, each to some adjacent cell. After each move, each end leaves a stone of that player's colour. The worm may not move onto a coloured cell.

If at some point before the board is full, a worm-end cannot move normally, the players continue, making single moves if necessary, until the next player who is able to must split the other end into two heads.

A player wins if he makes a 4 in-a-row with his stones (ortho or diag). If both ends become blocked simultaneously, the last player to move wins.

Sample Game:

J starts: sw.se  w.ne  n.s  e.nw  n.n  n.ne  w.n  w.se
ne.se  n.s  sw.s  sw.se se.s s.w   s.nw s.s ne.w?  e.n & wins

Final Position:

. . b . . . . .  
. j j b j b . .  
b b j j j b . .  
. j j b b b j .   
. b b j j j b . 
. j J B . . j . 
. b . . B j . b  
. . . . J b b j

TRI-HEX

2009-12-04T14:51:00.001Z

Each player drops a triangle group of 3 pieces (2 of its color) on empty cells. A triangle may also be dropped with pieces overlapping other triangles provided the colors do not change, and at least one previously vacant cell could not be filled by a regular move.

Sample Game:  
    ___xx_______oo__ (was swapped)
 1.  f4  ne    l8 n 
 2.  p6  sw    o9 ne
 3.  u7  sw    n4 s
 4.  j6  ne    s7*nw  
 5.  u5  sw    u11 n
 6.  z8  sw    u9 ne  
 7.  x6  sw    resign  

Final Position:

             X X X
: abcdefghijklmnopqrstuvwxyzABCDEFGHIJK  
| . . . . . . . . . . . . .             1
|  . . . . . . . . . . . . .            2
|   . . x . . . . . . . . . .  O        3
|    . o x . . x . . . . . . .  O       4
|     . . . x o o . x o . . . .  O      5
|  O   . . o x x o o x X O . . .        6
|   O   . . o o x o x o X . . . .       7
|    O   . . x . o . x o x o . . .      8
|         . . . x o . x o x . . . .     9
|          . . . . . o o . . . . . .   10
|           . . . . . x . . . . . . .  11
|            . . . . . . . . . . . . . 12
|             . . . . . . . . . . . . .  
: abcdefghijklmnopqrstuvwxyzABCDEFGHIJK    
                    X X X

Truncated Progressive Chess

2009-12-04T14:44:00.000Z

Basic progressive chess; but giving or releasing check, promoting or capturing
may not be done in a move series, except that the series be voluntarily
shortened to length one. (The subsequent series are unaffected.)

Sample Game:

1. e4
2. d5 e5
3. c4 d4 f4
4. Bg4 f5 Nf6 Nf3
5. a4 b4 h4 g3 Be2
6. h5h4h3 Bf3g2 Qe7
7. g4 g5 b5 Bf3 Ne2 Rg1 Nd1
8. Nb4 a5 b6 Ng4 g6 Bg7 c5 Rc8
9. B:g2
10. Nd3+
11. Kf1 (F)
12. Ne3++

Final Position:

. . r . k . . r
. . . . q . b .
. p . . . . p .
p O p p p p O .
O . O O O O . .
. . . n n . . p
. . . N N . B O
R . B Q . K R .

134*QUIKQUAX

2009-07-09T21:53:00.000+01:00

As soon as a diagonal pair appears, it automatically gets a diagonal join.
The moves in each series must be in different quadrants.

Sample Game:

             |                         OO|                XX--
a b c d e f g|h i j k l m n    
. . . . . . . . . . . . . .  1.  ..  ..  ..  e6     ..  i5  i10 e10
. . . . . . . x . . . . . .  2.  f7  i7  g10 l10    e3  m6  g8  h8
. X x . x . o . . . . . . .  3.  g3  h7  j8  f9     f5  h2  g12 h12 
. o . o x x . . x x x . X .  4.  g6  j5  e8  l12    c10 g5  h5  k9 
. . . o o x x x x o x o . .  5.  e5  k7  l8  f11    e4+ e12 k5  k11
. . . . o . o . . o o o x .  6.  d4+ l9  k6+ d9     c3  c12 k13 j4++
. . . . . o . o o . o . . .__7.  l13 l5+ d11 b4     b3  m4  d12 m12
. . . . o . x x . o . o . .  8.  OO resigns
. . . o . o . . . . x o . .  9. 
. . x . x . o . x . . o . . 10.  
. . . o . o . . . . x . . . 11.  
. . x X x . x x . . . o X . 12.  
. . . . . . . . . . x o . . 13. 
. . . . . . . . . . . . . . 14.  
a b c d e f g|h i j k l m n      
             |

QUADRATOLL

2009-07-07T09:44:00.001+01:00

Quadrex-connection game.
The winner is whoever joins two opposite groups of his own colour.

:   a b c d e f g h i j k l        XX   OO
:   o o o o o o x x x x x x        =======
: x . . . . x x x . . . . . o   1. h2   i5
: x . . . o x o . x . . . . o   2. g5   g7
: x . x o o o o . . . . . . o   3. f7   e7  
: x . x x x . x . . . . . . o   4. h7   h6+  
: x . . o . . . x . o . . . o   5. g8++ f6+ 
: x x . . . o o o o . . . . o   6. a7+  c9 
: o x . . . o x o x . . . . x   7. b8   e9
: o . x . . . x x x . . . . x   8. b10  g10
: o . . o . o . . . . . . . x   9. e2   c3
: o . x . . . . o . . . . . x  10. d4   f2
: o . . . . . . . . . . . . x  11. f1++ c5
: o . . . . . . . . . . . . x  12. b3   d2
:   x x x x x x o o o o o o    13. c4+  e3++
:   a b c d e f g h i j k l    14. f4   resign

TRIANGLE QUADREX

2009-06-08T14:30:00.002+01:00

Each turn, the player drops a tile of 2 of his own pieces and one
opponent piece that are not in deadlock position.  Single pieces
are added automatically as per quadrex rules.     If any cell is
unplayable by regular tiles, it may be played with an overlapping
tile, provided previous colours do not change.

Each turn, the player drops a mininmum-sized triangle of 2 of his own pieces
and one opponent piece that are not in deadlock position.  Single pieces
are added automatically as per quadrex rules.  If any cell is
unplayable by regular tiles, it may be played with an overlapping
tile, provided previous colours do not change.


| a b c d e f g h i j k l m n o    ___XXX_____OOO___
| x . . . x x . . . . . . . . . 1.  c3  es   b11 es
| o o o o o x o . . . . . . . . 2.  f10 en   h12 ne+
| . . o x o x . . . . . . . . . 3.  c8  se+  e10 nw+  
| . x x x o x . . . . . . X . . 4.  a9  en   b6  se
| o x o o o . . . . x x O O O . 5.  a8  ne+  d6  nw
| x x x x o x . . o x o o x x . 6.  c7  ne   f6  ws+
| x o o . o . . . . x o o o x . 7.  a5  en   a1  se  
| x x . . . . . . . . o x x x o 8.  c4  ..   e1  sw+
| o x o o o o x . . x o o x . . 9.  g2  ws+  f4  en
| . x x x x o x o o o o x x o . 10  l12 nw   n12 nw+
| . x o . . o o o x x x x o o . 11  i12 es   i11 ne++-
| . . o . . . x o o x . o o x . 12  n10 wn+  k5  ne
| . . . . . . . . . x . . . . . 13  i6  es+  j9  en+
| . . . . . . . . . . . . . . . 14  l9  ne   m6  sw+
| . . . . . . . . . . . . . . . 15  o8  wn+  m4  se+
| a b c d e f g h i j k l m n o 16  X resigns

OROUBORUS

2008-12-16T14:35:00.003Z

Players take turns moving both ends of the slime-worm, each to some
adjacent cell. After each move, each end leaves a stone of that
player's colour. The worm may not move onto a coloured cell.

If at some point before the board is full, a worm-end cannot move normally,
the next player who is able to must split the other end into two heads.

A player wins if he makes a 3 in-a-row with his stones.
If both ends become blocked simultaneously, the last player to move wins.

If, at one end, a player is left with only one move, (either physically
or because all others would lead to instant loss), the opponent who
left this situation must make the single move for his opponent,
and then another move for himself; recursively.

Game sample:



The first move recorded is from the most northerly cell,
and if in same line, most westerly.

B starts  
w.ne  w.nw  w.nw  ne.sw  ne.sw nw.se nw.se  sw.ne  w.e  sw.ne  e.e  ne.se  w.ne  nw.e   e.nw,nw,nw  & B wins

Final position:
|      . b . . .
|     b j j b . B
|    j b b j j B J    
|   . b j j b b j B  
|  . . j b j j b b j
|   . b j j b . j .
|    . . b . . . .
|     . . . . . .
|      . . . . .

GO-6-MOKU with restricted dagger

2008-10-22T22:08:00.001+01:00

Rules of 9x9 Go, except that there is no passing and the winner is
whoever gets a 6-in-a-row. Suicide is illegal, except that a 6-row
may be completed in an otherwise liberty-less position. No swap.

Neither dagger move may be used to capture, and they must finish
in different groups.

Sample Game

a b c d e f g h i     _XX____OO_
. . . . . . . . .   1. e5    f6  (O gets dagger)
. . . o o x . . X   2. f4    d6
x . o x x . x x :   3. e6    e7
. o . . . x . . x   4. e3    e2
. . o . x . . . .   5. f2    d2
. . o o x o . . .   6. d3    c3
. . . . o . . . .   7. h3    c5
. . . . . o . . .   8. g3    i3 
. . . . . . x . .   9. i4    b4,f8
                   10. a3,g9 c6
                   11. i2:   resigns

FLAT-EARTH DOZER-HEX

2008-09-29T19:31:00.001+01:00

Like Hex, but lines of friendly stones may push, abalone-wise, smaller lines of adversary stones by exactly their length difference.

If any stones block the full length of a push, the push stops there. A line may push its own length into empty space. Stones pushed off the edge disappear from the game. No friendly stones may be pushed. Swap option exists.

Sample Game


  
    OO    XX
 1. p4    p6     
 2. j6    l6     
 3. r6    n6     
 4. q5    o7     
 5. r4    n8     
 6. m9    n8s3   
 7. o5    m7     
 8. m5    s5     
 9. q3    m8     
10. n4    q7     
11. k5    u5
12. q3t6  o7s3   
13. p4v4   u7
14. s7     u5
15. q3     v8
16. p4     k9
17. n4     j10
18. s1     w7
19. n4v4:  s9
20. r8     t6v4:
21. q9     l6v6   
22. Resigns

Final Position:

   abcdefghijklmnopqrstuvwxyzAB
 ___________OO_________  
 \ . . . . . . . . . o \            1
  \ . . . . . . . . o o \           2
   \ . . . . . . . o x . \ X        3
    \ . . . . . . o o o x \ X       4
     \ . . . o o o x o x . \        5
     X\ . . o , , x x x o . \       6
      X\ . . . x . x o x x . \      7
        \ . . x . . o . x . . \     8
         \ . x o . o x . . . . \    9  
          \ x . . . . . . . . . \  10
           ----------------------  
                    OO

This game presents an Abalano-like mutator which seems to provide new games. Notice however that this mutator does not use the Abalone rule, since phalanxes can shift more than one cell (based on the difference between the pushed and pushing phalanx).

PRIME PICKINGS

2008-09-16T16:08:00.001+01:00

With 1 2 2 2.. modifier, each player picks 2 numbers from the available
number list, crossing them off afterwards.  He may place these numbers
anywhere in his board lists, at most 3 per list, or in an opponent list,
at most one per list.  Once 24 numbers have been entered, scoring is done
as follows:-  the row totals are added for each player, but only
the LARGEST PRIME FACTOR of this is entered as the row total.
The player of the 8th number may not make a tied contest there.

Whoever wins the majority of the three pile contests, wins the game.
........................
USEFUL PRIMES: 23 29 31 37 41 43 47 53 57 59 61 67 71 73 79 83
........................

Sample Game:

J starts: 
25, 24 23, 22 21, 20 19, 18 17, 16 15, 12 1, 14 6, 7 3, 
11 13, 5 10, 9 4 & B wins (it was the player's only option) 

                             primed
              player   oppt   score  winner
Board A:  B: 24 23  6    7      5
""""""":  J: 25 12  5   13     11      J

Board B:  B: 20 19 14    3      7      B
""""""":  J: 22 21 ..    9        

Board C:  B: 16 15 11    1     43      B     
""""""":  J: 18 17 10    4      7

Available numbers: 8  2

This is a very interesting number game. The last moves may become very demanding because each player must search a winning combination in a set of options big enough to be explored.

3/2 HEX

2008-08-22T09:14:00.002+01:00

On a unlimited stip of hexagons of height 7, one player (here X) tries to connect the two board edges while his adversary (here O) tries to prevent it.

The connecter plays two stones on each turn, provided that they do not belong to the same group of pieces. The preventer playes three stones on each turn with the same restriction.

If the connecter is unable to achieve his goal in 20 turns, he loses the game.

Game sample:



        __XX_________OO___ 
      1. H3 H5    G6 K6 I4
      2. D5 G4    E4 C6 I6
      3. D3 E6    C4 D7 L5
      4. F5 A6    G2 z7 F7
      5. B5 x7    K2 F3 y6
      6. B7 y4    y2 J1 A4
      7. v3 H1    I2 t1 w2
      8. z3 L3    A2 D1 J3
      9. E2 K4    J5 B1 w3
     10. w6 x3    u2 u4 z5
     11. t3 x5    r1 r3 o2
     12. N3 N5    O4 Q6 N7
     13. resign 

Final Position

   mnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUV
1   . . o o . . . o o . x o . . . . . .
2  . o . . o o o o . x o o . . . . . . 
3   . . o x x x x . x o x o x x . . . .
4  . . . . o o x o o o x o x . o . . . 
5   . . . . . x o x x x x o o x . . . . 
6  . . . . . x o x o x o o o . . o . . 
7   . . . . . x o x o o . . . o . . . . 
   mnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUV

This is a hex variant of different goals and powers, but which is quite balanced.

OROUBORUS

2008-08-08T09:24:00.000+01:00



J starts  
nw.e  w.se  w.ne ne.e   e.sw  nw.se
w.w sw.sw sw.w  se.w  se.ne   e.w  
B wins

Final Position:

       . . . . .
      j b . . . .
     b b j . . . .
    j j b j . . . .
   . b . .[b]j j b .
    . J B . . b j .
     . . B J . j b
      . . b j b .
       . . . . .

Y-MOKU

2008-08-05T11:24:00.001+01:00

The winner is whoever first makes
(i) a line of 5 (or more) adjacent stones of his own colour; or
(ii) a standard Y-connection of his own colour.
Swap option exists.

Game Example:


                              _XX_   _OO_(was swapped) 
            .              1. m11     m9
           . .             2. p10     j10
          . . .            3. o9      n8
         . . . .           4. p8      n10   
        . . . . .          5. o11     o7
       . . . . . .         6. l10     k9
      . . . . o . .        7. k11     i11 
     . . . x o x . .       8. s11     q11
    . . . o o x . . .      9. l8      h12
   . . . o x o x . . .    10. g13     f12
  . . . o x x x o x . .   11. resign
 . . o o . . . . . . . .  12. 
. . . x . . . . . . . . . 13.  
abcdefghijklmnopqrstuvwxy

Damello

2008-06-26T09:56:00.003+01:00

[A game between checkers and Othello sent by Giuseppe Acciaro]

The game is played on a 9x9 square board, where both players have 18 stones placed initially on their first two rows. There are four special red squares at D5/D8/B6/G6 (these are the coord given by the author, but they do seem too asymmetric).

Soldiers move vertically and diagonally. They capture with jump vertically and diagonally forwards. Capture is mandatory.

A Soldier that reaches the last row becomes a King, moving like in International Checkers except that it must land in the first square after each jump/capture.

When exactly one piece is between two enemy soldiers (orthogonally or diagonally), it changes color. If the piece is between at least one enemy King, then it is removed from board.

If any piece lands on a red square (either by move or capture) it is captured and removed from the board.

A player wins if the adversary cannot make a valid move.

A Progressive moku

2008-06-17T09:19:00.002+01:00

Played on a Go board. Black drops one stone, White then drops two stones, Black drops three, and so on...

A player wins if he makes a 5 in-a-row but he must just drop one stone in his last turn.

CHERRY

2008-06-17T09:08:00.004+01:00

Cherry is a Alak variant. First the rules of Alak:

This game is played on a 1-D line. Black and white alternate in placing single stones on a line of n points. If placing a stone thereby removes all the go-liberties of any group of stones of the opposite color, those stones are immediately removed. It is illegal to place a stone where one was just removed. Placing is compulsory if legal, and the game ends when the player having the move cannot legally place anywhere. The winner is the player with the most stones on the board at game end.

Cherry (invented by Bill Taylor, 2008) is played on a semi-infinite line segment where the first cell is marked (*):

* . . . . . . . . . . . . . ...

Wins the player the occupies the first cell with a friendly piece that cannot be captured by the adversary in the next move.

A sample game:


* . . . . . . . . . . . . . ...
* . x . . . . . . . . . . . ...
* o x . . . . . . . . . . . ...
x . x . . . . . . . . . . . ...

X wins because O cannot drop into the 2nd cell right now.

PUSH WOOD

2008-06-17T08:50:00.004+01:00

(by Richard Nowakowski, 2003)

Play on a line of N dots (this is an 1D game) each player has M pieces on the line extremes. For e.g., if N=9 and M=3:

x x x . . . o o o

On each turn, each player may:
* move forward a friendly stone to any empty cell or move out of the board (jumps are allowed).
* push a friendly stone backwards if it is backward adjacent to an enemy stone. Every stone in that group is pushed backwards any number of cells until it finds another stone. If there are no more stones, the player may even push out the group or part of the group over the line extreme.
* There is a KO rule: a player cannot repeat the previous position (variant: the player cannot push back any stone that was pushed back in the previous move).

Wins the last player that has a legal move.

A sample:


x x x . . . o o o
x x . x . . o o o
x x . x o . . o o
. x x x o . . o o
. x x x o . o . o
. x x . o x o . o
. x x . . o x o o
. x x . o x . o o
. x x . o x o . o
. x . . o x o x o
. x . . . . . . o
. . x . . . . . o
. . x . . . . o .
. . . x . . . o .
. . . x . . o . .
. . . . x . o . .
. . . . x o . . .

x resigns

Trabsact Sagme Diaries

2008-06-17T08:42:00.003+01:00

A game, when moved, usually travels with its own social context. For e.g., a game from the Trok planet, in the island of Mag, is played only by children with lemur-like and duck-like animals. Some centuries ago, the game went to a neighbor island, Dag, and, even if the rules changed a bit, the ducks and lemurs are also thrown by the Dag children. [T.Sagme, Travels]

GO-6-MOKU

2008-06-16T10:20:00.000+01:00

a b c d e f g h i      _oo__xx_
. . . . . . . . .   1.  b2  d4 
. o o o . O . . .   2.  d3  e4
. . x o o x . . .   3.  e3  f3
. x . x x o o . .   4.  c4  c5
. . x . x x . . .   5.  f4  c3
. . . . . . . . .   6.  c2  b4:
. . . . . . . . .   7.  d2  f5
. . . . . . . . .   8.  g4  e5
. . . . . . . . .   9.  f2  resign

FREE Y

2008-06-04T12:47:00.000+01:00

Swap option exists.
Winner is whoever makes a connected group that either
   (a) includes two nearly-opposite edge-points; or
   (b) includes three edge-points whose inter-point distances
                     are all less than half the circumference.

abcdefghijklmnopqrs     _oo_ _xx_  (after swap)
    . . o x . .      1.  g3   j6
   . . o x . . .     2.  k5   l6
  . . o x . . . .    3.  m5   n6
 . . . . . . . . .   4.  o5   p6
. . . o x o o o . .  5.  h6   i5
 . . . o x x x x .   6.  g5   i3
  . . . o . . . .    7.  i7   l8
   . . . . x . .     8.  h2   j2
    . . O . . .      9.  i1   k1?
     . . . . .      10.  i9   resign
abcdefghijklmnopqrs

Card Chess

2008-03-11T22:00:00.006Z

photo by Alexander Dzhantimirov
Imagination solves almost all
(the coordinates are wrong, but who needs perfection?)

PROGRESSIVE FENCES

2008-02-13T10:39:00.004Z

Cul-de-sac with L-shaped walls allowed.
Walls may be placed along edges, but not beyond them.
Win by crossing over the target edge.

The turns are progressively 1 2 2 3 4 4 5 6 6... moves, with a move being
one orthogonal step by the player's stone, or one length of 2-wall placement.
A player may distribute his available moves as he pleases (so placing a wall
costs two moves), subject to not being permitted to completely wall off
his opponent from his target.

Sample game (notation: Xy* means that a wall was placed at coordinate Xy with a certain shape given by symbol *. If * is 1,2,3 or 4 it means a L-shaped wall on the 1st, 2nd, 3rd or 4th quadrants; if * is - means a horizontal wall with center Xy; and if * is | means a vertical wall with center Xy):

1. S (Bottom)                   1         
2. NN                           2         
3. SS                           2         
4. N Fi-                        3         
5. Fh4 Hh3                      4         
6. Fd| Ge2                      4         
7. NES Hj2                      5         
8. He2 Hc| Fb3                  6         
9. Fj4 Ej| Gb2                  6         
10 Ib| Jc| Id- E                7         
11. NNNESSEN                    8
12. Kb3 Kd4 Je- Hk|             8
13. NEESSWSWW                   9
14. If2 Gf- Ef1 Ed| Dc1        10
15. SWWWNNNWNW                 10
16. SWWSSWN Bk- Dk-            11
17. SSSSSE Bg- Dg- Dj-         12
18. WWNNNEEE Fg1 Hg4           12
19. Eh1 E2E Df-  Bf1 Bd- Ce1   13
20. Bb| Cc- NWWW Jg2 Kg3 Ki-   14
21. Bottom resigns

Final Position
                    Top's goal
   A   B   C   D   E   F   G   H   I   J   K   L
 a + - - - - - - - - - - - - - - - - - - - - - + 
   :   |                   |       |           |
 b :   |   +   +   +---.---'   +   |   +---.   : 
   :   |       |       |       |   |   |   |   :
 c :   +-------`---+   +   +   |   +   |   +   : 
   :               |   |       |       |       :
 d :-------+   +   |   |   +   +-------+   ,---: 
   :       |       |   |   |   |           |   :
 e :   +   +---+   +   +---'---'   +-------+   :
   :   |           |               |           :
 f :   +---+-------`---+-------+---'   +   +   : 
   :     T             |               |       :
 g :-------+-------+   `---+   ,---+---'---.   : 
   :               |         B |           |   :
 h :   +   +   +   +---,---+---.   +   +   +   :
   :                   |       |               :
 i :   +   +   +   +-------+   +   +   +-------: 
   :               |           |               :
 j :   +   +-------|   ,---+---'   +   +   +   :
   :               |   |       |               :
 k :-------+-------+   +   +   |   +   +   +   :
   :                           |               :
 l + - - - - - - - - - - - - - - - - - - - - - + 
   A   B   C   D   E   F   G   H   I   J   K   L
                   Bottom's goal

QUADRAPHAGES

2007-12-17T23:15:00.000Z

Startup:

a b c d e f g h i   
. . O . . . . . .  1.  
. . . . . . . . .  2.  
. . . . . . . . X  3.
. . . . . . . . .  4. 
. . . . . . . . .  5.  
. . . . . . . . .  6.  
X . . . . . . . .  7.  
. . . . . . . . .  8.
. . . . . . O . .  9.

In each turn a player (a) moves his stones rookwise, the previous # of cells;
                      (b) announces a new number (between 1 and 8);
                      (c) moves his stones the new number of cells.

When a stone leaves a cell, it marks it with its own colour.
A stone may not land on a marked or occupied cell, or leave the board.
Given a number, stone must move if it can; if not, it remains stationary.
If possible, a player must choose a number that allows at least one stone
to move.

Intervening own-pieces or marks of either type do not block a move,
but opponent pieces do.  The first turn begins with operation (b) & (c) only.

The game stops when all four stones in succession fail to move; then...
the winner is whoever has the most marked cells.
"""""""""""""""""""""""""""""""""""""""""""""""

Game Sample


               _xx_                         _oo_
1.  ....  ....  1  a7a8  i3i2    c1c2  g9g8  3  c2f2  g8d8
2.  a8a5  i2i5  3  a5a2  i5i8    f2f5  d2d5  2  d5b5  f5f7
3.  a2a4  i8i6  7  i6b6  a4h4    ----  ----  3  b5e5  f7f4 
4.  i6i9  a4a1  8  a1i1  i9a9    ----  ----  4  e5e1  f4f8 
5.  ----  a9e9  6  i1i7  e9e3    ----  ----  3  e1h1  f8c8 
6.  e3h3  i7i4  1  i4h4  h3h2    h1g1  c8c7  5  c7h7  g1b1 
7.  ----  h4c4  4  h2h6  c4g4    h7d7  b1f1  5  f1f6  d7d2
8.  ----  g4b4  1  h6g6  b4b3    d2d3  f6e6  2  d3f3  e6c6
9.  ----  ----  4  g6g2  b3b7    ----  ----  3  f3c3  c6c9
10. g2g5  b7e7  1  e7e8  g5h5    c9d9  ----  2  c3a3  d9f9
11. ----  ----  6  ----  e8e2    a3g3  ----  4  g3g7  f9b9
12. ----  h5h9  2  ----  e2e4    ----  ----  1  b9b8  ----
13. h9h8  e4d4  3  ----  d4d6  and wins 40-39

Final Position:

a b c d e f g h i   
x o o . o o o o x  1.  
x . o o x o x x x  2.  
o x o o x o o x x  3.
x x x x x o x x x  4. 
x o . o o o x x x  5.  
. . o X o o x x x  6.  
x x o o x o O o x  7.  
x O o o x o o X x  8.
x o o o x o o x x  9.

This game can also be played on a hex-board. It has less
possible directions, so it's easier for a player to control
where the adversary may go, when the board starts to get full.

HEXAPHAGE
========= (numbers up to 6) Rules as for quadraphage.

               _oo_                         _xx_
1.  ....  ....     ....  ....    ....  ....  1  j5h5  d3e4
2.  g2f3  g6f5  1  f5d5  f3g4    h5i4  e4c4  3  c4f1  i4f7
3.  ----  g4m4  4  d5l5  m4j1    f7b3  f1b5  4  ----  b3j3
4.  ----  ----  3  j1d1  ----    ----  b5e2  1  e2c2  j3k4
5.  ----  l5k6  3  k6e6  d1a4    k4h1  c2i2  5  ----  h1c6 
6.  ----  ----  2  ----  e6i6    ----  ----  1  c6d7  i2k2
7.  resign

Final Position:

 abcdefghijklm   
    o x x o    1 
   x x o x X   2
  x x o . x .  3
 O x x o x x o 4
  x o o x x o  5
   x o o O o   6
    X x . .    7
 abcdefghijklm

AbGamers

2007-11-30T15:39:00.001Z

When we talk about abstract board gamers there is a relevant distinction. On one hand, there are people that don't mind giving lots of time and attention to abgames and, on the other, people that try an abgame or two from time to time. The first ones are hard to find and the net, like in r.g.a, is a perfect way for these guys (well, we) to meet and discuss and play abgames. It's difficult, if not impossible, to replace the net in this.

The second ones are much more common. There are thousands and thousands that like to play abgames. I live in Portugal, a country with no social history of abgames except for Chess and Checkers. From my experience, me and some local friends were able to promote abgames events alongside with hundreds of schools, where the finals alone gathered 500+ young people (we are preparing the 4th edition). We also made a set of 10 small books, discussing historical puzzles and games, that sold thousands for each copy. And Portugal only has a population of 10 million. I guess that from all these tens of thousands, some got interested and started reading and playing a bit more than before (I know that that happened at least in some cases). This is another way to contribute to the abgames future community.

[this blog has been too quiet, just like the main website, the World of Abstract Games. In these last months I didn't had much time to process new games (but I'm still collecting them) so be patient and check or recheck the 500+ pure abstract games already posted]

Sagme's Diaries

2007-05-23T22:00:00.000+01:00

With falling stones
many battles rage, but
the game is one.
[From Sagme's Haiku]

1222 UNRESTRICTED 6-MOKU

2007-05-17T22:38:00.000+01:00

Sample Game:

     XXXX        OOOO
00. --- o25     n24 n26
01. p24 p25     p26 o23
02. m25 n25     q25 l11 
03. o26 o27     q24 p27
04. o28 q26     n23 o29
05. l23 m24     k22 p23
06. q23 r22     s21 o22
07. m22 m23     m20 m26
08. n21 o20     p19 k24
09. j23 k23     i23 n19
10. l21 j24     o19 q19
11. m19 r19     p18 r20  
12. o17 t22     q17 n20
13. r16 j22?    p16 p17  
14. resign

Final Position:

g h i j k l m n o p q r s t u  
. . . . . . . . . . . . . . . 14
. . . . . . . . . . . . . . . 15
. . . . . . . . . O . x . . . 16
. . . . . . . . x O o . . . . 17
. . . . . . . . . o . . . . . 18
. . . . . . x o o o o x . . . 19
. . . . . . o o x . . o . . . 20
. . . . . x . x . . . . o . . 21
. . . x o . x . o . . x . x . 22
. . o x x x x o o o x . . . . 23
. . . x o . x o . x o . . . . 24
. . . . . o x x x x o . . . . 25
. . . . . . o o x o x . . . . 26
. . . . . . . . x o . . . . . 27
. . . . . . . . x . . . . . . 28
. . . . . . . . o . . . . . . 29
. . . . . . . . . . . . . . . 30
. . . . . . . . . . . . . . . 31

HIXT

2007-05-17T13:36:00.000+01:00

Rules:
* On his turn a player drop a friendly stones in an empty cell, and
connects it, via a bridge, with any friendly stone (at diamond's distance)
* Stones connect via adjacency or using a bridge
* PIE rule for the second player's first move
* The player connecting two opposite edges or making a Y connecting
three non-adjacent edges, wins the game

Sample Game:

XXX === OOO
j13     o8
h7      i10
l9      o10
l11     l7
k8      o12
j5      i6
g6      f7
d7      l5
m4      s4
q4      p3
p5      s6
p15     o14
m14     r15
c10     i12
g12     b9
c8      f9
d11     m2
g2      i4
j3      j1
h1 

1-0
 
Final position:

|a b c d e f g h i j k l m n o p q r s t u v w x y z A B C
|              x   o__ .   .   .   .   .   .                 1
|                     \__
|            x__ .   .   o__ .   .   .   .   .               2
|               \__         \__
|          .   .   x__ .   .   o__ .   .   .   .             3
|                     \__         \__
|        .   .   o   . __x__ .   x   o   .   .   .           4
|                   __/     \__      |
|      .   .   . __x __o   .   x   . | .   .   .   .         5
|             __/ __/                |
|    .   . __x __o__ .   .   .   .   o   .   .   .   .       6
|       __/ __/     \__
|  .   x   o   x__ .   o__ .   .   .   .   .   .   .   .     7
|          |      \__     \__
|.   x   . | .   .   x   .   o   .   .   .   .   .   .   .   8
|    |     |                 |
|  o | .   o__ .   .   x   . | .   .   .   .   .   .   .     9
|    |        \__      |     |
|    x   .   .   o   . | .   o   .   .   .   .   .   .      10
|                |     |     |
|      x__ .   . | .   x   . | .   .   .   .   .   .        11
|         \__    |           |
|        .   x__ o   .   .   o   .   .   .   .   .          12
|               \__          |
|          .   .   x__ .   . | .   .   .   .   .            13
|                     \__    |
|            .   .   .   x__ o__ .   .   .   .              14
|                           \__ \__
|              .   .   .   .   x   o   .   .                15
|a b c d e f g h i j k l m n o p q r s t u v w x y z A B C

Hixt is a hex variant of Twixt with some different connenction criteria. The board should be large enough so that the drama of a single bad move could not determine the match outcome. Probably, a hex board with edges of size 10 should already provide a nice battle.

A multiplication game

2007-05-02T09:23:00.000+01:00

This game is focused for young people when learning multiplication.
Let's consider multiplications x*y with values ranging from 1 to 9.

First, one player picks one pair, say x1*y1. The second player chooses another pair x2*y2. Then the second player takes the modulus of the difference , i.e., |x1*y1 - x2*y2| and takes that difference as his points. Then, the second player must choose a pair x2*y3 or x3*y2 (i.e., he must keep one of the numbers from his last picked pair). This is the first turn. Then this is repeated (now the first player starts choosing a pair, makes the difference and choose a related pair, and so on...). Pairs can never be choosed twice.

The game ends when one player cannot continue (there are no similar pairs to choose since all were selected already). The player with less points wins the game.

It's possible to speed things up but restricting to pairs x*y where x<y.

An initial example:


____ Player1 ____________ Player2 ____
--- (--------) 3x5 | 4x4 (1 points) 4x9 --> |3x5-4x4|=1
6x6 (0 points) 6x9 | 7x8 (2 points) 7x9
8x8 (1 points) 8x9 | 9x9 (9 points) 5x9
6x7 (3 points) 6x8 | 7x7 (1 points) 5x7
4x8 (3 points) 5x8   (and so on...)

Board Games Studies 2007 (part 3: The Spielmuseum)

2007-05-01T09:22:00.000+01:00

The game museum, near Vienna, is a project from Dagmar de Cassan and her husband. Nowadays, it consists of thousands of games that are being archived and cataloged in a digital database. Let's hope they can solve the space problem so that people can consult and play many of these board games.

Board Games Studies 2007 (part 2: The Talks)

2007-05-01T08:58:00.000+01:00

There were several talks at the Colloquium ranging from psychology, history (we heard, for instance, about the history of Draughts, Go and Liubo), regional games (some films in India and Zanzibar where game masters play Bao) and math (the connections between math theories and chess).

Here are some pictures of one talk that defends that the Ashtapada board was not used to play any specific race game and how the round board found in the Kurna temple does not represent any game:

Another talk presented a study from Alex de Voogt about the tactical similarities and differences between beginners and masters in the complex mancala game of Bao.

The next talk showed some boards and regional designs of an old race(?) game called Liubo from China (the rules, seemingly, are lost).

Board Games Studies 2007 (part 1: The Games)

2007-04-30T23:26:00.000+01:00

Last week at St. Pölten, a small city near Vienna, it took place the 10th Board Games Studies Colloquium. It is a chance to meet several different people around board games (historians, inventors, collectors...). Here are some games that I found out there:

These first two are two games rescued from the Netherlands's patent office in the 80's by Fred Horn (a prolific game inventor, a jazz musician and a great guy). The first game (for 2 or 4 players) uses a Go-like rule to capture every group that's unable to move. The second uses hidden-information so that the special stone can move into the farthest cell (jumps over enemy stones flip them and make them friendly pieces).

This is an old Stratego-like game:

This is a new edition of a card set designed by Descartes himself (!):

A geometrical game where players have an equal set of pieces all with the same volume (48 units) and each piece cannot be adjacent to another piece of the same height or color and identical pieces must be placed differently (the picture shows an invalid position, both yellow pieces are placed in the same position).

This next one is a connection game called ConHex by Michail Antonow:

Patterns @ Conimbriga

2007-04-19T23:09:00.000+01:00

Conimbriga is an archeologic site of an ancient Roman villa at the center of Portugal. Here are some photos and some of its interesting floor tilings.

CHOSEN CHESS

2007-04-02T16:31:00.000+01:00

[by João Neto] In normal Chess you choose a piece, then you move it. In Chosen Chess, when it's your turn, you move the (previously chosen) piece, then you choose another piece (for the next move).

In the first move White choose a (movable) piece, then Black do the same.
In the subsequent moves players move the chosen piece (if possible), then choose a different piece.
No Check, checkmate or en-passant.
Castling is a King move.
The player that captures the adversary King wins the game.

BEAT IT OR EAT IT

2007-03-30T12:35:00.000+01:00

[Bill Taylor 1993 post @ r.g.a] Though this games is played with cards, and is (very vaguely) one of the trick-taking family of games, it still belongs here in rec.games.abstract. It is as much a strategy game as sprouts, chess and Go, being a 2-player game of complete information with no element of chance (apart from the starting layout, and even this is symmetric between the players).

Long ago, I played a (more complex) version of this game, for a while. The original game was a 4-suit game, each player having his own trump suit. However this 2-suit version seems just as skillful, as much fun, and "cleaner". It is even possible to play a one-suit version !!  No other changes in the rules are needed, except that the starting layout can no longer be symmetric. But the two-suit version seems neatest.

I post it here because...

(i) it deserves to be far better known than it is;
(ii) it seems to be essentially unique of its kind;
(iii) I would eventually be keen to start an email game or two.

The game has been around a fair while, but doesn't seem to have a name of its own. It was first introduced to me as "Besicovitch's game", but such a name is hardly descriptive. We sometimes used to call it "Finchley Central" as a small in-joke, indicative of the hair-trigger timing needed to decide when to strike your main blow. The game usually see-saws one way then the other, as every advance tends to leave one weaker. Thus it might fairly be called "See-Saw" or "Negative Feedback".  Until a concensus is reached, I shall call it "Beat It Or Eat It"; being descriptive of the mechanics of play.

One nice thing about the game is its almost complete freedom from *arbitrary* rules, once the basic logic of play is set. The main exception is the length of the suits.  13 is the obvious length, and feels about right. Shorter would be good for practice games, and longer (up to 26) would be possible, with one "red" suit and one "black" suit.

The core idea of the play is:- taking the lead in turns, one player leads and the other follows, until someone gets rid of all his cards, thus winning.

--------------------------------------
"BEAT IT OR EAT IT"  (Full rules)

1. Two players play with a deck of 13 hearts and 13 spades. Aces count high.

2. The initial layout is symmetric, and obtained thus:-  One player shuffles, and deals 13 cards to the other, who keeps only the red cards. The blacks are returned to the undealt cards, and the dealer gives himself black cards identical to his opponent's reds. Then each gets the remainder of the other color. The "leader", (player of the 1st card), is chosen at random.

3. The leader plays any card onto the table. The follower EITHER picks it up,  OR (if he can, & wishes to), beats it by playing a higher card of the same suit. These cards stay on the table, and the follower becomes the leader for the next play.   Continue with (3) again.

4. On any play, the follower may, if he desires, (& must, if unable to beat the card led), pick up all the cards on the table, and add them to his hand. The leader then remains as leader for the next play.  Continue with (3).

5. Whoever first plays the last card left in his hand, is the winner.
  (It is immaterial whether this occurs as a lead or a follow.)
-------------------------------------

So, the idea is to get rid of all your cards. But it is essential along the way to sometimes (voluntarily) pick up all the tabled cards, to get some of the high ones there, (even though this hinders your main goal, of course).

And often, (especially if the opponent is close to winning, or has too few low cards for comfort), you will have to lead a high card that he CAN'T beat, forcing him to pick up all the junk on the table.

Remember, all played cards, leaders and beaters, stay on the table (face up), until one player chooses to or is forced to "eat" them, i.e. pick them all up, and suffer being follower again for the start of the next series of plays. As long as no-one "eats" the stuff on the table, the lead alternates.

So there it is. It is a great game; and as I say, one of complete information. In fact it is standard for both players to keep their hands face up on the table in front of them, for convenience; (these hands are only on the physical table of course, not the "logical" table).  If you try it out, you will quickly notice the negative feedback element mentioned above.

It is usually an advantage to start, but by no means always; it depends on the nature of the starting layout, and perhaps on the parity of the suit length.

I warmly recommend everyone to give it a try.

To indicate the nature of the play, here is a sample game, with a 7-suit pack.

Initial layout: (LEFT has the opening lead)

LEFT: hearts A Q T 9 8      RIGHT: hearts K J
      spades K J                   spades A Q T 9 8

8h, Jh. 8s, Js. 9h, Kh. 9s, LEFT eats all (by choice).


Layout now:  (RIGHT is on lead)

LEFT: hearts A K Q J T 9 8     RIGHT: hearts -
      spades K J 9 8                  spades A Q T

Ts, Js. 8h, RIGHT must eat. 9h (R must eat). Th (R must eat).

Layout now:  (LEFT is still on lead)

LEFT: hearts A K Q J      RIGHT: hearts T 9 8
      spades K 9 8               spades A Q J T

8s, Ts. 8h, Jh. 9s, Js. 9h, Qh. Kh, RIGHT must eat all.

Layout now:  (LEFT is still on lead)

LEFT: hearts A       RIGHT: hearts K Q J T 9 8
      spades K              spades A Q J T 9 8

Ah (right must eat);  Ks and LEFT WINS.

This game hardly showed much ability on either part. RIGHT should have
struggled more actively in the last phase of play, e.g. when he led the 9h, which led to an immediate simple forced loss. But it was probably too late by then anyway. There was a very clear-cut error earlier. When RIGHT led the ten from his 3-card hand of AQT hearts, it would clearly have been uniformly better to lead the queen. (However he was probably lost anyway.)

LEFT also made a blunder in the very first round; he could have beaten the 9s with the Ks, led back the Th (compulsory eat), the Ah (ditto) & Qh (winning). (Suit length of 7 is not really enough to give the full flavor of the game.)

FANO NIM

2007-03-24T14:22:00.000Z

[bill Taylor, 2005] Here's a cute little mathematical game. I'm surprised it hasn't been around the abstract game world before. It's only the second game I know of that's based on the Fano plane - the smallest possible 2D Projective Geometry.

Here it is - it has vertices THEY WAR, and lines YEA WHY TRY HER RAW WET HAT,
neatly compiled into a triangle with three altitudes, and an incircle which
is also a "line"...

                           Y
                          /|\
                         / | \
                        /  |  \
                       /   |   \
                      /    |    \
                     / _.-"|"-._ \
                    /.'    |    `.\
                   H.      |      .E
                  /: "-.   |   .-' :\
                 / |    ";-T-:"    | \
                /  :  _-'  |  `-_  :  \
               /    \'     |     `/    \
              /  ,-' `.    |    .' `-.  \
             /_-'      `-..|..-'      `-_\
            W--------------R--------------A

Note there are no interior intersections between the altitudes and
the circle, only at the tangent points where they triply intersect
with the sides as well.

Anyway, the game is a form of Nim.

The diagram starts with a small integer at each of the seven vertices,
the number of "seeds" at that vertex, preferably a different one for each.
(These can be decided on in one of several standard ways.)

On each turn, the player to move must remove THE SAME number of seeds from
any three vertices in a line, (remembering that the circle is also a line).

Last person to make a legal move wins. (This is the standard
winning condition for CGT games. There is also the "misere" version OC.)

I will leave it as a fun exercise for fans to compile a list,
hopefully exhaustive, of all the "N positions" (Next player wins),
and all the "P positions" (Previous player wins).

And note, too, that if one too quickly learns the correct optimal play,
(though it is not as straightforward as regular Nim), one can easily
extend it to larger projective geometries; (the next one has 13 lines
comprising four vertices each and meeting four at a vertex.)

It can, OC, be played on any geometry at all; but the projective
nature of the game ensures that the winning condition is equivalent
to producing a line of zeros, which is a nice target to aim for!

BESIEGE

2007-03-24T13:57:00.000Z

[by João Neto] Start with the NxN board full of stones. Then, alternating moves,
each player removes a stone (that stone is not captured) When a player makes a
square, he captures all the stones inside that square (no diagonal squares).

E.g.

x x x x x   5
x . x x .   4
x x x x x   3
x x . . x   2
x . x x x   1
a b c d e

If a player removes stone e1, he will capture stones c3 and d3

When there are no capturable stones left on the board, wins the player
with more captured stones.

Area vs Territory Go Rules

2007-03-24T10:40:00.001Z

[Bill Taylor] The following Go example shows a safe set of stones with two eyes:

. . . . . .
. . o o . .
. o o . o .
. o . o o .
. . o o . .
. . . . . .

Would this set be called a single group even though it is composed of two disconnected halves?

Most players would call it a single group. In area rules it doesn't matter what you call it. In territory rules it could conceivably matter what you call it, (though it doesn't in practice), because territory rules, in all their artificial absurdity, have to refer to groups from time to time in order to define what is considered "dead" and what is considered "alive".

In territory rules, this matters(!). In area rules, it doesn't matter - if there is any dispute you just play it out (and with no cost) until a group or groups is removed from the board.

Logically speaking, you should call the above two separate groups, each helping to keep the other alive. But people never speak so precisely in practice.

There is even a worse situation. The following group has only one true "eye"; the other one, in the NW corner, is a so-called "false eye", and can eventually be filled and the whole lot captured.

. x x . o .
x o o o o o
x x x x o .
x . x x o o
x x x x o .

Territory rules actually have to define the concept of eyes, false eyes, and the rest. It is lunacy. (Area rules define nothing - you just play it out to the grim end if necessary). Territory rules, with their defined false eyes, come to grief in this famous sort of position:

. x x x x x | Here, black has TWO false eyes, and not a single true one!
x o o o o x | And yet, both separate groups, or parts of a group, are
x o o . o x | keeping one another alive; rather like your above example.
x o . o o x |
x o o o o x | And even the Japanese admit that black is alive, in spite of
x x x x x . | what their rule books say!

Basically, territory rules are an abortion. Computers cannot handle them because they are essentially logically flawed.

Games Operators, aka, Mutators

2007-03-24T10:25:00.000Z

[Posts@rec.games.abstract ~ Dec 99, Jan 2k]

[Douglas Zare] Here are five examples of operators on games:

1) Misere: The object of the new game is to lose while playing the old game.
2) Move and switch: After the first move, the second player can choose to switch sides rather than respond.
3) Bad advice, as in Fred Galvin's "Compromise Chess": A player offers two possible moves to the opponent, who advises the player which to play. If there is only one legal move then this is simply made.
4) Use a doubling cube, as in backgammon. I have heard that this is a nice addition to speed chess, and would guess that this would make spectator sports more interesting.
5) Bughouse: Instead of playing, you can drop in a piece your partner has captured on a parallel color-reversed board. The partnership of the first winner wins.This doesn't do much for go or pente, but how does it affect checkers?

All of these take in games and produce new games, though there may be a few choices to make in the implementation. In my experience, understanding the original game carries over to some level of understanding in the new game, although there are substantial differences. Interestingly, the first three are close to involutions, i.e., applying the operator twice may produce the original game. The first three also produce legal games, albeit strange ones, and can be played on many internet game servers to the confusion of kibitzers. (I'm always willing to play backgammon misere unrated as zare_10027 on Yahoo.)

I am curious what other interesting operators have been tried, particularly those which are simple, preserve some of the structures of the original game, and are fun. I would also appreciate any pointers to annotated games or the theory of hex misere and backgammon misere. (Are there videos of grandmasters playing bughouse?) On the other hand, I would like to know how much the endgame theory of bad advice go resembles that of ordinary go.

[Tim Chow] John Conway has suggested "Whim," which is Nim except that at any point in the game a player may say "Whim" instead of moving; this decree alters the game from normal to misere. The whim may be invoked only once per game (*not* once per player per game). It turns out that Whim is just Nim with an extra "invisible" pile of counters (I forget of what size) representing the whim, but the same operator will surely have more interesting effects on other games.

[David Bush] Misere doesn't work well for chess and related games. Selfmate puzzles notwithstanding, it's usually impossible to force your opponent to checkmate you. Misere Go sounds like a disaster. Checkers might be interesting, with cumpulsory captures. Maybe Misere suicide chess, where captures are compulsory and the King is just another piece, but the last player to move WINS...? Speaking of which, suicide might be an applicable operator to battle games. There are tons of fairy chess rulesets which might apply to battle games (chess, checkers, etc.) For example, unambiguous chess requires all moves to be representable unambiguously with 3 symbols in descriptive notation, where the dash - doesn't count, but the x for captures does. E.g. you couldn't play QR-K1 if KR-K1 is also possible. Maybe some games have move notation which could be adapted for this. Or, salt shaker chess starts the game with a salt shaker on a central square. The shaker moves in the same direction & distance as whatever piece is moving (king when castling.) You may not move the shaker off the board with your move. The issue of what2do if the shaker would land on an occupied square, could be dealt with in several ways. Then there's nuclear chess, where each piece adjacent to a capture, friend or foe, is removed from the board (except the capturing piece.) Or protean chess, where each piece (except possibly the king) takes on the powers of movement of whatever piece it captures. Or et cetera...

[Fred Galvin] Here are some references on misere hex (and other variants):

Ronald Evans, A winning opening in Reverse Hex, J. Recreational Math., Vol. 7, No. 3 (Summer, 1974), 188-192.
Ronald Evans, Some variants of Hex, J. Recreational Math. Vol. 8(2) (1975-1976), 120-122.
Jeffrey Lagarias and Danny Sleator, Who wins Misere Hex?, in: Scott Kim, ed., Articles in Tribute to Martin Gardner (Atlanta International Museum of Art and Design, January 16, 1993), 146-148.

[anonymous] you can pre-give an amount of -say- money to each player. Whenever such a predefined condition occurs , both players bet from their money , whether they want the condition to be valid or cancelled , and the highest bet decides. Of course this bet-amount is substracted from the higher-bet-player's money. This usually increases (and sometimes completely changes) the structure of the game. As an example consider betting tic-tac-toe , where always the player moves , who bets most. Or betting go : after move 3n , the n-th free square is filled with a piece from the player whith the higher bet. Or betting football : all 10minutes a player is removed from the team whith the lower bet. A handicap for good-players can be applied by allowing different initial amounts of money.

[Andy Tepper] How about a HoardMoves(G,n) operator? At any time instead of moving you may delay up to n moves and then make them all at once in the future. For instance, in HoardMoves(Go,1) you could skip a turn and then play the two moves in parallel on some future turn. A group would have to have 3 eyes to be alive. (Assuming moves were made in parallel. You could always say that the two moves must be made in sequence which keep the 2 eyes rule.)

[Gerry Quinn] Sounds a bit horrid in Chess. Both players will hoard at the start, with White hoping to declare mate in (say) ten, and Black having to scramble for some tactics to prevent it. But then Black will be further behind, and White will win when he has hoarded a couple more. As Alekhine said (or was it Nimzowich) "In Chess, the threat is stronger than the execution!" Hoarding a _partial_ move might be interesting in Chess, though. Pass a move twice, and you have a free one in hand. This might be fairly balanced.

Nice Chess Sites

2007-03-23T22:07:00.000Z

About the Origins of Chess

http://www.mynetcologne.de/~nc-jostenge
http://www.samsloan.com/origin.htm

About Tournament Chess

http://www.mark-weeks.com/chess/55571wix.htm
http://www.chesscafe.com/

Curiosities

http://www.xs4all.nl/~timkr/chess/chess.html

Go and the 'Three Games'

2007-03-23T21:46:00.000Z

Go and the 'Three Games' -- A text by William Pinckard

Games-playing is one of the oldest and most enduring human traits. Disparate pieces of evidence such as dice discovered at Sumer, game-boards depicted on Egyptian frescoes, Viking chess pieces, and ball parks constructed by ancient empires deep in the Andes link up directly with contemporary phenomena such as Saturday night poker games in Kansas City and the annual go title matches in Tokyo.

Games are undeniably a concomitant of civilization and even in their most primitive forms presuppose some degree of sophistication. Most of all, they require the ability to think in abstractions and to manipulate ideas in logical terms, thereby giving form to what is formless and creating small, recognizable patterns in the shadow of great mysteries.

From ancient times in Japan the so-called `Three Games' were backgammon, chess and go. Chess probably comes from India, backgammon from the Near or Middle East, and go from pre-Han China. Backgammon is a gambling game which, using dice, gives luck or chance the preponderant role. Chess in one of its earlier forms also used dice, but takes its present shape from the structure of a royal society and from war maneuvers. Go is the most abstract and `open' of the three; and with its freedom from complicated rules, its simplicity of form, its fluidity and spaciousness, it comes remarkably close to being an ideal mirror for reflecting basic processes of mentation.

Go is played with black and white `stones' all of exactly the same value, thus somewhat resembling the binary mathematics which is the basis of the computer. The stones are played onto the board and are left as they stand throughout the game, so that the game itself takes shape as a visible record of the thinking that went into it. About three hundred years ago an eminent Chinese monk came to Japan on a visit and was shown the diagram of a game of go which a master of that time had recently played. Without knowing anything of the game save the sketchy description they gave him at the time (this was after go had more or less died out in China), the monk studied the moves as shown on the record and after a few moments remarked with much admiration and respect that the player must have been a man who had become enlightened -- which was indeed the case. (It is interesting to note that this story is told on the one hand by go players to illustrate the quality of the game and on the other hand by Buddhists to show the acuity of the monk from China.)

The great 17th century Japanese playwright Chikamatsu, in a famous passage, compares the four quarters of the go board to the four seasons, the black and white stones to night and day, the 361 intersections of the board to the days of the year, and the center point on the board to the Pole Star. It would be easy to erect a tower of fanciful theory along these lines, but that would only obscure the obvious point. In this striking analogy Chikamatsu is describing a feeling of hugeness and all-inclusiveness -- the board conceived as a complete world system in potential form. The board and pieces can be thought of as limitless: any number of lines and an endless supply of stones to play with, the game itself being the life of the players. (In Chikamatsu's play a young man becomes old and grows a long beard while watching a single game.) Only because we are human and must put practical limits to our activities, do we use just a small part of the infinite board. But this field of nineteen by nineteen is large enough to contain everything we are able to put into it. The number of possible games playable on this board has been reckoned to be more than the number of molecules in the universe.

An anonymous go player has written: `The board is a mirror of the mind of the player as the moments pass. When a master studies the record of a game he can tell at what point greed overtook the pupil, when he became tired, when he fell into stupidity, and when the maid came by with the tea.'

Contrary to the opinion of many people, go has nothing to do with Buddhism. Because it is a valid system in itself, it offers nothing contradictory to other systems, but in fact go is an older inhabitant on this planet than is Buddhism. In China it became one of the Four Accomplishments, the others being poetry, painting and music. It reached Japan around the 6th century and for a long time remained the exclusive property of a leisured noble class. Then during the 16th century all this changed. The many great families and clans which had warred happily against each other for a thousand years were gradually brought under the hegemony of the Tokugawa Shogunate. It was during the subsequent period of the Tokugawa era (roughly from 1600 to 1868) that go, along with haiku, kendo, tea ceremony and so on, was most actively cultivated as a way of constructively channeling the mental energies of the people during the long years of peace. One formal word for go in Japanese is Kido. Ki is the old Chinese word for go, and -do is the Chinese word for Tao, which means Way -- or, more specifically, a Way to enlightenment.

All games channel mental energies, whether they lead to enlightenment or the reverse, but it is suggestive to consider the `Three Games' in their social context because then we can see how each of them reflects certain basic characteristics of a general or regional type.

Chess, for example, the great historical game of the West, involves monarchs, armies, slaughter, and the eventual destruction of one king by another. The game appears to be entirely directed along the lines of the great myths of the West from the Mahabharata to the Song of Roland -- the overthrow of a hero and the crowning of a new hero. The pieces, from king down to pawn (peon), give a picture of a heirarchical and pyramidal society with powers strictly defined and limited.

Backgammon, the favorite game of the Near and Middle East, is preoccupied with the question of Chance and Fate (Kismet). All play is governed by the roll of dice over which the player has no control whatever. The players are matched against each other, but each tries to capture a wave of luck and ride it to victory. The loser curses his misfortune and tries again, but the individual is helpless in the grip of superior forces.

Go, the game of ancient China and modern Japan (and now popular throughout the world), is unique in that every piece is of equal value and can be played anywhere on the board. The aim is not to destroy but to build territory. Single stones become groups, and groups become organic structures which live or die. A stone's power depends on its location and the moment. Over the entire board there occur transformations of growth and decay, movement and stasis, small defeats and temporary victories. The stronger player is the teacher, the weaker is the learner, and even today the polite way to ask for a game is to say `Please teach me.'

Things are different now, but in earlier times, when go was so much admired by painters and poets, generals and monks, the point of the game was not so much for one player to overcome another but for both to engage in a kind of cooperative dialogue (`hand conversation', they used to call it) with the aim of overcoming a common enemy. The common enemy was, of course, as it always is, human weaknesses: greed, anger and stupidity.

Every year in March department stores all over Japan present elaborate displays in connection with the Doll Festival. If one looks carefully at the miniature weapons, musical instruments and furniture of a really complete display one will find a tiny backgammon board, a Japanese chess (shogi) board and a go board.

The `Three Games' is a useful classification because taken together they make up a coherent world view. Most of philosophy boils down to speculation centered around the three basic relationships of the human species. The first is man in his relationship to the remote gods and the mysterious forces of the universe. The second is man in the society he builds up around him. The third is man in his own self. Or, to put it another way, man the backgammon-player, man the chess-player, and man the go-player.

That we have these three shows that they answer basic needs in the human spirit. People everywhere are preoccupied with social structures, position and status; and everyone who is capable of reflection must sometimes speculate on his private relationship to fortune and fate.

But go is the one game which turns all preoccupations and speculations back on their source. It says, in effect, that everyone starts out equal, that everyone begins with an empty board and with no limitations, and that what happens thereafter is not fate or wealth or social position but only the quality of your own mind.

Seo's unknown game

2007-03-23T21:33:00.000Z

[Seo Sanghyeon mathmaniac@hanmail.net] This game (name and author unknown) is played on square grid board of odd size. But don't choose smaller than 3x3. It's trivial. 5x5 with two players is interesting enough, but 7x7 is more strategic, I think.

EQUIPMENT: I strongly recommend to play by paper and pencil. It's hard to play with board and stones. Since there is no capture, no need for eraser.

INITIAL POSITION: Each player chooses start position, and drop his stone there.

DROP: On each turn, each player drops a stone on an empty cell adjacent, orthogonally or diagonally, to his last dropped stone. And board wraps, i.e. first row is adjacent to last row, etc. And draw (this is why paper and pencil is recommended) a link from his last dropped stone to his newly dropped stone. When playing diagonally adjacent cell, this link should not be crossed.

. . . . 
. o 1 . 
. x , . 
. . . .

If 'x' plays '1', a link from 'x' to '1' is drawn, and since it cannot be crossed, 'o' cannot play ','.

..  o2 o3 o4 
..  o1 ,,  o5 
..  x.  o7 o6 
..  ..  ..  ..

On the other hand, if 'o1'-'o7' is played in that order, there is no link from 'o1' to 'o7', so 'x' can play ','. So that's why playing with board and stones is ambiguous.

A variant

..  ..  ..  .. 
..  x1 x3 .. 
..  ,,  x2 .. 
..  ..  ..  ..

According to the rule described above, now 'x' cannot play ',', because 'x1' to 'x2' link will be crossed. But there's a variant that allows crossing of his own link. And it seems this leads to more interesting game on 7x7.

EXAMPLE GAME:

'x0', 'o0' is initial position, i.e. diagonally opposite corner. Since board wraps, there's no difference between corner and center. But wrapping moves are harder to read. 'x' plays first.

x0 ..  x5 o5 o6 
o7 ..  x4 x6 x7 
x8 ..  x3 ..  ** 
..  x2 o2 o1 ..  
..  x1 o3 o4 o0

(o8: resign)

COMMENT:

x2-x3 prevents white to move toward upper left corner. x5 is of same line, preventing o4-x5 wrap move. And notice that, after o7, o cannot play marked ** cell, since it will cross x7-x8 link.

. . / . . . . 
\ x . x o o . 
\ o . x x x \ 
. x . x . . \ 
. . x o o . . 
. . x o o o . 
. / . . | . .

If you draw board this way, It's not that hard to see. (It can be done on TwixT board, too.) So, white has at most three cells to play, but black has five.

. . / . . . . 
\ x 5 x o o . 
\ o 3 x x x \ 
. x 1 x . . \ 
\ 2 x o o 6 . 
. 4 x o o o \ 
. / . . | . .

Also notice that

x0 ** x5 o5 o6 
o7 :: x4 x6 x7 
x8 ..  x3 ..  ..  
..  x2 o2 o1 ..  
## x1 o3 o4 o0

o cannot play o7-**-## line, since it crosses x0-x1 link. Therefore
:: as a reply to ** is a mating move.

RingGo 80% Go 20% Hex

2007-03-23T21:21:00.000Z

[(C) 2001 William I. Chang] RingGo is a variant of Go played on a hexagonal lattice with 127 points, 18 of which are removed from play in order to strike a balance between how easy or hard it is to make a group of stones live. The board inherits from Rosette, Medusa, and especially a conversation with Greg Van Patten. Most points have 4 liberties. While it is harder to make two eyes, it is easier to connect groups so the network may have two eyes. In this sense, I think the game achieves its goal of combining Go's intricate eye-making tactical play with the connection-making strategy of Hex (though perhaps not enough of the latter). I'm sure it can be refined and improved if more people tried it. The board is generalizable to odd-order lattices by repeating the Medusa pattern, although there are lots of other beautiful patterns to choose from.

           . . . . . . .                  . . . . . . . . .
          . . . . . . . .                . . . . . . . . . .
         . . . o . o . . .              . . . o . o . o . . .
        . . o . . . . o . .            . . o . . . . . . o . .
       . . . . . o . . . . .          . . . . . o . o . . . . .
      . . o . o . . o . o . .        . . o . o . . . . o . o . .
     . . . . . . . . . . . . .      . . . . . . . o . . . . . . .
      . . o . o . . o . o . .      . . o . o . o . . o . o . o . .
       . . . . . o . . . . .      . . . . . . . . . . . . . . . . .
        . . o . . . . o . .        . . o . o . o . . o . o . o . .
         . . . o . o . . .          . . . . . . . o . . . . . . .
          . . . . . . . .            . . o . o . . . . o . o . .
           . . . . . . .              . . . . . o . o . . . . .
                                       . . o . . . . . . o . .
             . . . . .                  . . . o . o . o . . .
            . . . . . .                  . . . . . . . . . .
           . . . o . . .                  . . . . . . . . .
          . . o . . o . .
         . . . . . . . . .
          . . o . . o . .     RingGo boards of order 5/7/9, with 55/109/193
           . . . o . . .      points.  The order-11 board has 301 points.
            . . . . . .
             . . . . .

One might play RingGo on a Go board if one can envision dividing each
square into two triangles with a diagonal line drawn top-left/bottom-right.
(There actually was a commercial version of Hex done this way!) Or, have
the players sit adjacent and both look toward the *.

   . . . . . . .           *
   . . . . . . . .
   . . . o . o . . .
   . . o . . . . o . .
   . . . . . o . . . . .
   . . o . o . . o . o . .
W   . . . . . . . . . . . . .
     . . o . o . . o . o . .
       . . . . . o . . . . .
         . . o . . . . o . .
           . . . o . o . . .
             . . . . . . . .
               . . . . . . .

               B

This game should play very differently from other hexagonal Go variants.
I tried and liked it :-) Any suggestions or comments will be greatly
appreciated!

William Chang Los Gatos, California 18 April 2001
email: wchang@acm.org, williamichang@hotmail.com
(C) 2001 William I. Chang

---

Other Boards:

Rings board

          o o   o o   o o
         o   o o   o o   o
          o o   o o   o o
       o o   o o   o o   o o
      o   o o   o o   o o   o
       o o   o o   o o   o o
    o o   o o   o o   o o   o o
   o   o o   o o   o o   o o   o
    o o   o o   o o   o o   o o
       o o   o o   o o   o o
      o   o o   o o   o o   o
       o o   o o   o o   o o
          o o   o o   o o
         o   o o   o o   o
          o o   o o   o o

Medusa board

          o o o o o o o o
         o   o   o   o   o
        o o o o o o o o o o
       o   o   o   o   o   o
      o o o o o o o o o o o o
     o   o   o   o   o   o   o
    o o o o o o o o o o o o o o
   o   o   o   o   o   o   o   o
    o o o o o o o o o o o o o o
     o   o   o   o   o   o   o
      o o o o o o o o o o o o
       o   o   o   o   o   o
        o o o o o o o o o o
         o   o   o   o   o
          o o o o o o o o

Revolving Games

2007-03-23T21:16:00.001Z

Finding ways to spin your games
or
The stable King and his revolving servants

[December 2000] We (Bill Taylor and Joao Neto) have invented and started to play some games wth a common rule theme: if some condition is met, the moved piece changes its powers. Like a game with rotating officials.

This, if done well, can result in very dynamic games, where some pieces lead very wild lies.

Joao invented a game based on a simple idea: depending whether the turn number is even/odd, the moved piece is promoted/demoted. This basic change makes (in Joao's opinion) a very good chess variant, called Promotions and Demotions, or just ProDem.

But, is this the only possible way to use this dynamic idea?

Revolving Games

There is an old chess variant, named Revolving Chess (whose origins we don't know), whose rules are:

REVOLVING CHESS

1. Same as FIDE, except:
2. Each moved non-king piece, changes its status in the following order:
  2.1. Knight to Bishop,
  2.2. Bishop to Rook
  2.3. Rook to Queen
  2.4. Queen to Knight

--------------------------------------------------
The original game was fully "royal", but we play with stalemate
= win for stalemater, though still with castling (R changing to Q).
--------------------------------------------------

Game Sample

1. d4      d5      
2. c4      d:c4    
3. Nc3(B)  b5      
4. a4      c6      
5. a:b5    c:b5    
6. b3      a5      
7. b:c4    b:c4    
8. e3      R:a6(Q) 
9. Ne2(B)  e5      
10 B:c4(R) Bd6(R)  
11 R:c8(Q)  Qa:c8(N)
12 B:a5(R)  e:d4    
13 Rb5(Q)+  Nc6(B)  
14 Q:c6(N)  R:c6(Q) 
15 Q:d4(N)  Q:d4(N) 
16 e:d4     Nf6(B)  
17 Bf4(R)   O-O(Q)  
18 Ra6(Q)   Qc2(N)+ 
19 Kd2      N:d4(B) 
20 R:f6(Q)  B:f6(R) 
21 Q:f6(N)+ g:f6
22 Ba6(R)   Kg7
23 Rha1(Q)  Qe8(N)
24 Ke3      Ncd6(B)
25 R:d6(Q)  N:d6(B)
26 h3       Be5(R)+
27 Q:e5(N)  f:e5
28 Ke4      f3
29 Kf5      Kf7 
30 g4  1-0 [if Ke7 or Kf7 then h4]

Final Position: 

. . . . . . . .
. . . . . k . p
. . . . . p . .
. . . . p K . .
. . . . . . O .
. . . . . . . O
. . . . . O . .
. . . . . . . .

--------------------------------------------------

Since it's the older game, we may think of it as the standard revolving positional game in this text, despite the fact that Promotions and Demotions was an independent discovery. In fact, ProDem was the first game we played, and it was then that many different and yet related ideas appeared.

Firstly, the rules of ProDem:
-----------------------------------------------------
PROMOTIONS & DEMOTIONS [aka "even-up, odd-down"]

1. The FIDE rules apply except in the following:
2. On even turns, a moved (non king) man is promoted after move completion.
3. On odd turns, a moved (non king) man is demoted after move completion.
4. The Promotion/Demotion system has this ordering: P < N or B < R < Q.
5. Pawns on the 1st rank may move 1 or 2 squares.
6. Pawns on the 8th rank cannot move, but may be captured.
7. There is no En-Passant, Mate, Check or Castling.
8. The winner is whoever first captures the opponent's King.
9. White does not play on turn 1.

notes:

* A Pawn can promote to Bishop or Knight at the mover's choice.
* A Rook can demote to Bishop or Knight at the mover's choice.
* Queens cannot be promoted, so they cannot move on even turns.
* Pawns cannot be demoted, so they cannot move on odd turns.
* Since every pawn promotes when moving, there is no FIDE promotion.
* Black must start, with a Knight's demotion.
(helps neutralize 1st move advantage).
----------------------------------------------------

Here goes two sample games:

1.   --     Nf6(P) 
2.   c4(B)   e6(B) 
3. B:e6(P)  Qe7(R) 
4. e:f7(B)  R:B(Q) 
5.  Qc2(R)  Nc6(P) 
6.   g3(B)   h5(N) 
7.  Bg2(P) N:g3(P) 
8. f:g3(B)   d6(B) 
9. B:d6(P) B:d6(P) 
10  Nf3(R)   d5(B) 
11.  Rc5(B)  Rh4(N)
12.  Nc3(R) N:g2(R)
13.  Rb1(B) B:a2(P)
14.  Bh7(R)  Bc6(R)
15. Rhf1(B)  Rg6(N)
16.  Bg2(R)   a6(N)
17. R:g6(B) Q:g6(R)
18. Rh8(Q)+  Kf7
19. Qxa8(R) Nxc5(P)
20.   b3(B)   b5(B)
21. B:e6(p)+  Kd7
22. R:c5(Q)+  K:e6
23. Rf5(B)+   Kf7 
24. Rf8(Q)+   1-0

Final Position: 
. . . . . Q . .
. . p . . k p .
. . p . . p r .
. b Q . . B . .
. . . . . . . .
. . . . . . . .
p . . O O . . O
. . B . K . . .

[note: even if these games have non royal Kings, we still use the + symbol which means some piece is attacking the King]

1. --        Nc3(P)      
2. b3(B)     d5(B)       
3. Bb2(P)    Bf5(P)      
4. c4(B)     e6(B)        
5. Ne3(P)    Bc4:B(P)    
6. h4(B)     c4:B(B)     
7. Bh4:Q(P)  Bb3:Q(P)    
8. Nc3(R)    Ra8:P(Q)    
9. Rb1(B)    g6(B)       
10.Bb1xB(P)  Be6:P(P)    
11. g6:f7(B)+  K:f7         
12. Rh5(B)+    Ke7          
13. d3(N)      a5(B)        
14. Kd2        Ba:Rc3(P)+   
15. b2:c3(B)   Nf6(R)       
16. Ke1        Rg8(B) 
17. g4(N)      Rf5(Q) 
18. Bf6(P)+    Qxf6(R) 
19. Ne5(R)+    Re6(Q) 
20. R:Qe6(N)   K:e6 
21. Be8(R)+    Kd7 
22. Re8e5(N)+  Ke6 
23. Bh3(R)     a1(B) 
24. Kf1        B:e5(P)
25. resigns    0-1

Final Position: 

. . . q . b b . 
. p p . . . . p 
. . p . k . . . 
. . . . p . . . 
. . . . . p N . 
. . . . . O . R 
. . . . O O . . 
. . . p . K . .

Other remarks:

* The Rook is probably the strongest piece. It may move any turn, and still transforms into a strong piece.
* A (possibly good) method of play would be to always move your king on odd moves, so your piece strength constantly went up and never down. Hwever, this would waste so much time it probably wouldn't pay off anyway, since a player doing that increases his army, but slows by half its efficiency.
* Of course, making the other player moves his King on a even turn, makes him lose a promoting turn.
* A pawn on the last rank cannot move. That is especially bad, since the other player can use it as a protecting wall.

**********************

Well, taking different behavior given a turn number is one possibility, others exist:

which colour square the piece is on
which colour square the piece goes to
whether the piece changes square colour when it moves
whether the piece moves forward or back (allowing no promotion for sideways)
whether the piece has any immediate neighbours or not
whether the piece is making a capture or not

These options can be divided into two groups, where the game is completely defined by presenting:
a) merely the board and the next player
b) the board and the next player and some extra information (like the turn number as in ProDem)

Notice that in this classification, FIDE Chess belongs to group b), as it may be necessary to state that a King is moved (for castling) or if some pawn was moved (to make en passant capturing). We both feel that group a) games are more elegant, (but that does not mean dropping the others!! :)

With that last point as motivation, Bill invented the next game:

------------------
MOVE UP, TAKE DOWN
~~~~~~~~~~~~~~~~~~
1. All men move as in chess, except there is no castling or en passant.

2. Movement is compulsory, and once his king is captured a player loses.

3. Once a move is made, that piece immediately changes into the next one up this cycle -  P to N to B to R to Q to P; except if it was a capture,
then the order is the opposite.

4. A pawn on the 1st rank may move 1 or 2 spaces if not capturing.
  A pawn on the 8th rank may never move again, but can be captured.

5. If there are no pawns on the board before a move is to be made,
  the order changes to N B R Q N, (or its reverse for captures).
------------------

We would like you to specially notice rule 5. Its motivation was to ensure that a board with no pawns would no longer require knowledge of its *orientation*, similar to the "no-external-info" mentioned above. However, it has resulted in a new idea:- that when a certain condition is true (no pawns), the game dynamics changes. This is not a common feature in Chess Variants, but may be an excellent concept to extend.

And here goes a sample game

1. g4(N)   d5(N)  
2. e3(N)   f6(N)  
3. Ne:N(P) Q:d5(R)
4. b4(N)   b6(N)  
5. c4(N)   a6(N)  
6. N:f6(P) e:f6(Q)
7. N:b6(P) c:b6(Q)
8. Be2(R)+ Be7(R) 
9. N:d5(P) Q:a1(R)
10 Nc3(B)  Nf6(B) 
11 B:a1(N) B:a1(N) 
12 R:e7(B) K:e7    
13 Ba3(R)  Bd7(R)  
14 Nf3(B)  Rd6(Q)  
15 Rd3(Q)  Nc5(B)  
16 Be4(R)+ Kd8     
17 Rh4(Q)+ Kc7     
18 Q:a1(R) B:f2(N) 
19 Q:f2(R) Q:f2(R) 
20 K:f2    Ra7(Q)+ 
21 Ke2     Re8(Q)+ 
22 Kd1     Na6(B)  
23 Rf1(Q)  B:d3(N) 
24 Q:d3(R) g5(N)   
25 h4(N)   Ne4(B)  
26 Rc3(Q)+ Kd8     
27 Nf3(B)  B:d5(N) 
28 B:d5(N) Q:d5(R)
29 a3(N)   h6(N)
30 Nc4(B)  Q:a1(R)+
31 Q:a1(R) Ng4(B)+
32 Kc2     R:d2(B)
33 K:d2    Qe4(N)+
34 Kd3     Nd6(B)?
35 Bg8(R)+ Bf8(R)
36 R:g4(B) Rf6(Q)
37 Ra5(Q)+ 1-0

Final Position: 

. . . k . . . .
. . . . . . . .
. . . . . q . .
Q . . . . . . .
. . . . . . B .
. . . K . . . .
. . . . . . . .
. . . . . . . .

SloPro LISBON

2007-03-22T08:22:00.000Z

Winner is who first makes a connected group touching three non-adjacent
sides; or one touching two opposite sides; or closed circuit surrounding at least one space or opponent stone. 122234445666... moving with different-group restriction. Corners belong to both sides.

Sample Game:

OOO starts
 1. p7
 2. m6 m8
 3. n7 n9
 4. l9 q8
 5. p5 o8 n11
 6. o6 r7 m10 q10
 7. j7 p3 k12 o10
 8. m4 j5 q6  s10
 9. g4 g6 k7 h10 q12 
10. h3 k4 f5 j11 t11 t13
11. h5 j3 k6  m2 n5  r9
12. f2 k2 o2 v13 l5  t9 
13. u8 i4 n3 v11 p9 s12 k10
14. h1 l3 h7 l11 v7 u12 v15 x9
15. n1 r5 u4 k14 u6 q14  s8 y8 
16. j1 s2 i8 t15 z7 p11  z9 m12 
17. c6 i6 w6 w10 A8 s14 A10 w14 A6
18. e4 t5 f7 t7  B7  a8  d9  B9 g10 o12
19. b9 j9 o4 t3  w8  y6 x11 e10 h11 u14
20. s4 e6 x7 c8 i10 y10 d11 g12 y12 j13
21. C8 d7 f9 r3  y4 e12 i12 i14 n13 n15 x13
22. f3 x3 v5 z5 c10 z11 f13 l13 o14 h15 l15 r15
23. e8 v9 h13 p15 & resign

Final position:

abcdefghijklmnopqrstuvwxyzABC    
       x x . o . . . .           1
      x . x o x . x . .          2
     x x o x o o o o . x         3
    x o o x x o . x o . o        4
   . x o x x o o o x x . x       5
  o x o o o x x x . o o o o      6
 . o x x o o o o x x x x x x     7
x x o . x : x o x o o o o o o    8
 o x o o o x o o o x o x x x     9
  x o x x o x o x x . o x o     10
   x . o x x o x . x o o x      11
    o x o o x x o o x - x       12
     x o x x o . . x x o        13
      . o o - x o o o o         14
       x . x oo x x x          15
abcdefghijklmnopqrstuvwxyzABC

XXX wins at k8 and then either f11/m14 next turn

DISPATCH GAMES

2007-03-20T09:42:00.000Z

Dispatch is a game, or set of games, where starting with a stone on board, the player orthogonally dispatches a seed to another empty cell and then grows a pattern (usually a mino, like a tetrominoe or a pentominoe). Check the rules here.

Here are two games:

TETROMINOE DISPATCH

       XXX              OOO
  1. c3-h1234        c9-j8h8910 
  2. h4-h567,g78     j3-j4567 
  3. g8-g9,10,11,f11 c9-b234c4 
  4. h5-d4bcd5       c9-de9e1011
  5. g8-cdef8        c9-b789a7 
  6. c8-abc6c7       j3-j12kl1 
  7. c3-abc1c2       j8-k891011 
  8. a1-a2345        resigns 

   a b c d e f g h j k l 
1  x x x . . . . x o o o 
2  x o x . . . . x o . . 
3  x o x . . . . x o . . 
4  x o o x . . . x o . .  
5  x x x x . . . x o . . 
6  x x x . . . . x o . . 
7  o o x . . . x x o . . 
8  . o x x x x x o o o . 
9  . o o o o . x o x o . 
10 . . . . o . x o . o . 
11 . . . . o x x . . o . 
   a b c d e f g h j k l 

PENTOMINOE DISPATCH 
 
       XXX              OOO
  1. c3-l12345      m3-m456kl6 
  2. l5-jk5j6jk7    c13-l13,lmno12 
  3. c3-abcde12     l12-cdef11f12 
  4. k7-lmn7n56     c11-bd3bcd4 
  5. c3-cde2e34     f11-e5f2345 
  6. e2-efg1g23     f5-f6789,f10 
  7. b12-b7891011   f4-g4,h1234 
  8. c2-a2345       b4-a678b56 
  9. l1:m1mn2n34    c11-c10,9876 
 10. k7-k11121314l1 f10-jklm10m9 
 11. k11-hj11h8910  f12-gh12h131415 
 12. e12-efg13g1415 f6-gh5gh6h7 
 13. h9-jklmn9      o12-no10o98p8 
 14. h8-jklmn8      l12-l1415m14n1314 
 15. n4-o4567p7     c13-d13def14f15 
 16. b12-b1314c1415d15   h4-j4k1234
     draw 30-30 (!)

  a b c d e f g h j k l m n o p 
1  . . . . x x x o . o x x . . . 
2  x x x x x o x o . o x x x . . 
3  x o x o x o x o . o x . x . . 
4  x o o o x o o o o o x . x x . 
5  x o . . o o o o x x x . x x . 
6  o o o . . o o o x . . . x x . 
7  o x o . . o . o x x x x x x x 
8  o x o . . o . x x x x x x o o 
9  . x o . . o . x x x x x x o . 
10 . x o . . o . x o o o o o o . 
11 . x o o o o . x x x x o . . . 
12 x x x x x o o o . x o o o o . 
13 . x o o x x x o . x o . o . . 
14 . x x o o o x o . x o o o . . 
15 . . x x . o x o . . o . . . . 
   a b c d e f g h j k l m n o p

Sacrifice Mutator

2007-03-20T09:35:00.000Z

Sacrifice Reversi (by Patrick Duff) is a Reversi variant with an extra rule: Instead of making a regular Reversi move, a player can choose to flip one of his own stones on board. There's also a KO rule to avoid repetitions.

This idea is a game mutator, it can be extended to modify many other games. Reversi Draughts or Reversi Chess could make a difference in some positions. Other games, like Moku or Hex would not produce interesting variants, since there's no position where an enemy piece is better than your own stones. I'm not sure about Reversi Go. Could it be possible to make a position where an enemy stone is better than a friendly one?

Meta-Game

2007-03-20T09:29:00.000Z

Nick Bentley sent me an idea for a meta-game with an automatic balacing mechanism, which is called Mind Ninja:

Take any boad which begins empty. The game proceeds in 5 steps

Player 1 decides three things, which he must convey to player 2:

what the pattern will be;
whether the builder or blocker will receive free moves in step 3;
how many free moves that player will receive.

Then, player 2 decides which player is the builder, and which is the blocker.
Either the builder or blocker takes free moves as specified in step 1.
Starting with the builder, the players alternate moves.
The game ends either when the board is completely full or the pattern has been built. If the pattern has been built, the builder wins. Otherwise, the blocker wins.

More hex-mokus

2007-03-16T21:36:00.000Z

M u l t i m o k u

Go Moku on a 3.4.6.4. tiling

There are 6 rows through each hexagon, 4 through each square and 3 through each triangle.  The ratio of Hexagons:Squares:Triangles = 1:3:2, so the average number of rows through a cell is 4 as in standard Go Moku.

(The 4.6.12 tiling gives the identical game as the 3.4.6.4. tiling. Each dodecagon has 6 rows, hexagons have 3 rows, squares have 4. The topology of the game is the same.)

In this ascii representation, 'H' is the center of a hexagon, 'S' is the center of a square and 'T' is the center of a triangle: 

        . . .
       .     .
  . . .   .   . . .
 .     .     .     .
.   H   T . .   .   .
 .     S     .     .
  . . .   .   . . .
 .     .     .     .
.   .   . . .   .   .
 .     .     .     .
  . . .   .   . . .
       .     .
        . . .

Illustration of rows -->

Each hexagon 6 rows through it:

        . 1 .
       .     .
  . . 6   1   2 . .
 5     6     2     3
.   5   6 1 2   3   .
 .     5     3     .
  4 4 4   H   4 4 4
 .     3     5     .
.   3   2 1 6   5   .
 3     2     6     5
  . . 2   1   6 . .
       .     .
        . 1 .

Each square has 4 rows through it:

        . . 2
       1     .
  . . .   2   . 3 .
 4     1     3     .
.   4   2 3 .   .   .
 .     S     .     .
  . 3 2   4   . . .
 3     1     4     .
.   2   . . .   4   .
 .     1     .     4
  2 . .   .   . . .
       1     .
        . . .

Each triangle has 3 rows through it:

        . . 2
       .     .
  . . 1   2   . . .
 .     1     .     .
2   2   T 2 2   2   2
 .     2     .     .
  . . 2   1   . . .
 .     .     .     .
.   2   . . 1   .   .
 .     .     1     .
  2 . .   .   1 . .
       .     .
        . . .

The 4.6.12 tiling gives the identical game as the 3.4.6.4. tiling. Each dodecagon has 6 rows, hexagons have 3 rows, squares have 4. The topology of the game is the same.

        Proposed board for Multi-Moku
           Three move equalization
    No 3-3 or other placement restrictions

   abc d efg h ijk l mno p qrs t uvw x yzA B CDE
 1                     . . .
 2                    .     .               1)l13     p15
 3               . . .   .   . . .          2)t17     swap or play
 4              .     .     .     .
 5         . . .   .   . . .   .   . . .
 6        .     .     .     .     .     .
 7   . . .   .   . . .   .   . . .   .   . . .
 8  .     .     .     .     .     .     .     .
 9 .   .   . . .   .   . . .   .   . . .   .   .
10  .     .     .     .     .     .     .     .
11   . . .   .   . . .   .   . . .   .   . . .
12  .     .     .     .     .     .     .     .
13 .   .   . . .   X   . . .   .   . . .   .   .
14  .     .     .     .     .     .     .     .
15   . . .   .   . . .   O   . . .   .   . . .
16  .     .     .     .     .     .     .     .
17 .   .   . . .   .   . . .   X   . . .   .   .
18  .     .     .     .     .     .     .     .
11   . . .   .   . . .   .   . . .   .   . . .
20  .     .     .     .     .     .     .     .
21 .   .   . . .   .   . . .   .   . . .   .   .
22  .     .     .     .     .     .     .     .
23   . . .   .   . . .   .   . . .   .   . . .
24        .     .     .     .     .     .
25         . . .   .   . . .   .   . . .
26              .     .     .     .
27               . . .   .   . . .
28                    .     .
29                     . . .

Hex-mokus

2007-03-16T21:19:00.000Z

Moku games (ie, achieve n in-a-row pattern to win) are usually played on square boards with four directions (horizontal, vertical and two diagonals). When translating to a hex board there are one problem, hex tillings only have three directions, which is too few, so the direct translation of hex-moku is a very drawish game, since there are no space to create winning positions with multiple threats. One way to prevent this is to use six directions to win, extending the types of lines inside the board. Here are some possible examples with sample games, including a standard three directions (which ended in a not so surprinsing draw):

Triangular Go Moku on the vertices of a hexagonal grid.
Winning rows in six directions.

   AB CD EF GH IJ KL MN OP QR ST UV WX YZ ab
 1                     . .                   
 2                  . .   . .                
 3               . .   . .   . .             
 4            . .   . .   . .   . .          
 5         . .   . .   . .   . .   . O       
 6      . .   . .   . .   . .   . .   . .    
 7   . .   . .   . .   . .   . .   X .   . . 
 8  .   . .   . .   . .   O .   . X   . .   .   
 9   . .   . .   . .   . .   X O   O .   . .    
10  .   . .   . .   . O   . X   X .   . .   .   
11   . .   . .   . .   O X   X X   X O   . .    
12  .   . .   . X   . X   X O   . .   X .   .   
13   . .   . .   . O   X O   O .   . .   O .    
14  .   . .   . X   O O   O .   . .   . .   .   
15   . .   . .   . O   . O   . .   . .   . .    
16  .   . .   . X   . .   . O   . .   . .   .   
17   . .   . .   . .   . .   X X   . .   . .    
18  .   . .   . .   . .   . .   . .   . .   .   
19   . .   . .   . .   . .   . .   . .   . .    
20  .   . .   . .   . .   . .   . .   . .   .   
21   . .   . .   . .   . .   . .   . .   . .    
22      . .   . .   . .   . .   . .   . .       
23         . .   . .   . .   . .   . .         
24            . .   . .   . .   . .            
25               . .   . .   . .               
26                  . .   . .                  
27                     . .                   

"O" won with a row at M10, N11, O13, P14, Q16

HEX Go Moku I (winning rows in 3 directions)
                 
Sample Game:
                    
    XXX OOO
 1. i9   j10    
 2. i10  j11    
 3. j9   k9     
 4. i8   i7
 5. i11  i12
 6. h7    k10
 7. g6   f5
 8. h8   j12
 9. h9   j13
10. j14  h6
11. j8   g8
12. k8   l8 (f)
13. f9   g9 (f)
14. h11  h10(f)
15. h12  i13
16. k13  i5
17. g5   g3
18. j6   i3
19. i4   f6
20. f4   k5
21. j5   j7 (forced)
22. j4   n10 Draw

           . . . . . . . . .         1
          . . . . . . . . . .        2
         . . . . . . O . O . .       3
        . . . . . X . . X X . .      4
       . . . . . O X . O X O . .     5
      . . . . . O X O . X . . . .    6
     . . . . . . . X O O . . . . .   7
    . . . . . . O X X X X O . . . .  8
   . . . . . X O X X X O . . . . . . 9
    . . . . . . O X O O . . O . . .  10
 a   . . . . . X X O . . . . . . .   11
  b / . . . . X O O . . . . . . .    12
   c   . . . . O O X . . . . . .     13
    d / . . . . X . . . . . . .      14
     e   . . . . . . . . . . .       15
      f   . . . . . . . . . .        16
       g   . . . . . . . . .         17
        h /     /     /              
         i j k l m n o p q           


HEX Go Moku II with 3 move equalization (winning rows in 6 directions)

Sample Game:

    XXXX       OOOO 
 1  g11        m9
 2  s7         m7
 3  m11        j8
 4  p10        p6
 5  g9         n8
 6  l10        o7
 7  q5 (f)     k7 wins in 3
 8  i7 or q7   l8 (double 3)

abcdefghijklmnopqrstuvwxy    
             -               1
          - - - -            2
       - - - - - - -         3
    - - - - - - - - - -      4
 - - - - - - - - X - - - -   5
  - - - - - - - O - - - -    6
 - - - - -(O)O O - X - - -   7
  - - - - O - O - - - - -    8
 - - - X - - O - - - - - -   9
  - - - - - X - X - - - -   10
 - - - X - - X - - - - - -  11
  - - - - - - - - - - - -   12
 - - - - - - - - - - - - -  13
    - - - - - - - - - -     14
       - - - - - - -        15
          - - - -           16
             -              17

I see now that 5) ... n8 wins in 4 always ending the same double three at l8. Since 5) g9 (or s5) was forced, the 4) ... p6 wins in 5. The first two 'X' moves I suggested didn't even slow 'O' down.

More information at http://www.di.fc.ul.pt/~jpn/gv/hexgomoku.htm.

SCALA

2007-03-16T14:30:00.000Z

Scala is a little-known abstract game published in 1986 by Skill Games.
It has features reminiscent of Halma, Camelot, and Lines of Action.

RULES. The game is played with the following setup:

14           [o]
13          . . .
12       . . . . .
11      . . . . . . .
10    . . . X X X . . .
09  . . X X X X X X X . .
08  . . X X       X X . .
07  . . O O       O O . .
06  . . O O O O O O O . .
05    . . . O O O . . .
04      . . . . . . .
03        . . . . .
02          . . .
01           [x]
   a b c d e f g h i j k

* GROUP - A set of connected (orthogonally or diagonally) stones.
* TURN - On each turn, each player moves or jumps one stone.
  + MOVE - A stone may move to any adjacent (orthogonal
           and diagonal) empty cell.
  + JUMP - A stone may also jump over any stone (friend or foe)
           landing on the opposite empty cell (it must be empty).
           A player may make on the same turn, multiple jumps with
           the same stone, and may change direction after each jump.
  + It is not valid to move or jump to its own first cell.
* CONNECTION - After each move or jump, any stones not connected
              (orthogonally or diagonally) to another stone of the
               group is captured.
* CAPTURE - If, after a move or jump, the group is divided, the
            larger of the remaining groups containing pieces of both
            colors survives.
           The smaller group, or the group containing pieces of a
            single color are removed from the board.
           There is only one connected group on the board, after
           each move.
           Some other restrictions:  It's not valid
           to produce two groups with the same number of stones,
           if both groups have stones of both colors.
           It's not valid to separate the two colors completely.
* GOAL - Wins the player who advances one stone into the opponent's
        first cell (the cell marked in the first diagram with a
         color dot).

More information at http://www.di.fc.ul.pt/~jpn/gv/scala.htm

Game Sample

      Final Position
14          [O]             1. f5-h5-j7       d9-b7-d5-f5
13         . O .            2. d7-d9-f11      f9-d9-d7-d5
12       . O X . .          3. d6-b8-d10      f10-h10-j8-j6
11     . . . O . . .        4. h6-j8-h10-f10  d8-b6-d6-f4
10   . . . X O . . . .      5. f6-d6-b6-d8    c9-c8
09 . . . . X . O X . . .    6. c7-c9-e11      g10-h10
08 . . . .       O O . O    7. f10-g10        h10-f10-f12
07 . . . .       . O O .    8. d8-f10(:bc8)   g9-h10
06 . . . . . . . O X . .    9. g5-h6          h10-j8
05   . . . O . X X . .     10. i7-g9          i9-i7-g5
04     . . . X . . .       11. g6-i8          f5-h5
03       . . X X .         12. h6-i7          j8-h6
02         . X .           13. e6-e4-g4-g6    d5-f5-f3(:c6)
01          [o]            14. g10-e12        h6-h4
  a b c d e f g h i j k    15. d10-d11        h4-h3
                           16. i6-k8          j6-i6
                           17. g6-h6          h8-j6
                           18. h7-h8          j6-i5
                           19. e11-e13        i5-h4
                           20. d11-f13        h4-h2
                           21. e13-f14        resigns, 1-0

SCORING HEX-MOKU

2007-03-16T14:26:00.000Z

Played on a 8 sided hex board, each player gets 1 point for each 4 in-a-row made. The player that gets 7 points or a 5 in-a-row wins the game. Initially, one player drops 3 stones (2 blacks and 1 white) and the adversary decides color (black starts the game).

Sample Game:

    XXX  OOO
 1) k2   o8     
 2) m2   q8     
 3) o2   q2     
 4) i2+  g      
 5) k5   s8     
 6) m8   u8+
 7) w8   k4
 8) m4   n3
 9) n5   l3
10) j5   p5
11) h5   f5
12) k6   l7
13) j7   i8
14) i6   g4
15) k8   l9
16) g6   e6
17) i4   j3  (forced)
18) f7   e8  (forced)
19) m6   o6  (forced)
20) h3 & wins 7-1

Final Position:

   abcdefghijklmnopqrstuvwxyzABC

 1        . . . . . . . .       
 2       O X X X X O . . .      
 3      . x o O O . . . . .     
 4     . O x O X . . . . . .    
 5    . O X X X X O . . . . .   
 6   . O X X X x o . . . . . .  
 7  . . x . X O . . . . . . . . 
 8 . . o . O X X O O O O X . . .
 9  . . . . . O . . . . . . . . 
10   . . . . . . . . . . . . .  
11    . . . . . . . . . . . .   
12     . . . . . . . . . . .    
13      . . . . . . . . . .     
14       . . . . . . . . .      
15        . . . . . . . .

Projective Hex

2007-03-16T13:33:00.000Z

[Bill Taylor: This article is chiefly for rec.games.abstract; but I cross-post to sci.math for the possible interest in tilings of Projective Planes]

One of the great blessings of connection games like Hex and Bridgit is, that victory is certain for one or other side, AND the structure of the game ensures that a victory for one is *automatically* a defeat for the other, with no special rule needed to say so.  So there is no element of a mere "race" to do something first, where both players might achieve this goal almost simultaneously.

Although there is no "social" defect in such races, (e.g. even chess can be so viewed - a race to capture the opponent's king before he captures yours), it is mathematically and game-theoretically slightly unaesthetic, compared to the Hexlike feature of   [win = not(loss)]   by structure.

Hex and Bridgit both suffer from another slight unaestheticity though, to wit, that the two players have (slightly) different tasks; one must make a North/South connection, and the other an East/West one.   Indeed, in Bridgit they even play on different points!  Again, this is no barrier to playing the game or to its being a jolly good game, but again it seems a very slight aesthetic defect.

One game that achieves both goals, i.e. (1) complementary winning conditions and (2) identical tasks; is the excellent "Y" version of Hex, which really deserves to be better known.  However, I introduce yet a new variant here.

------

Some while ago, Dan Hoey and myself jointly invented a game we called PROJECTIVE HEX, invented in this newsgroup, in fact.

It was Dan who, partly inspired by "Y", first ventured onto Projective Planar boards for Hex-like games, but couldn't find a nice winning condition, surprisingly. My contribution was to observe that the condition of making a GLOBAL LOOP, (i.e. a closed path that crossed the boundary an odd number of times) was "THE ONE" - and that it stood out "like a sore thumb". Dan agreed about the sore thumb, and kicked himself for not having seen it before. Dan also constructed a program to print out beautiful Hex-like boards based on the Projective Plane, and thus having 6 pentagons amongst a variable number of hexagons.

My latest contribution has been to change the pattern of the boards slightly, to make them more homogeneous-looking (though not fully homogeneous in fact), and thereby arrange it so that games can easily be played at the keyboard, i.e. by email etc.

For the new Projective Hex, now probably the best abstract board game in the world (ha-ha!), the boards are similar to this as follows...

   A B C        As you see I've had to insert a 27th alphabet letter!
  D E F G       Interior cells and interior-edge cells each have 6
 H I J K L      neighbours, as in Hex; but the 6 corner cells have 5.
M N O # P Q
 R S T U V      The side dimensions are always n and n+1.   Each edge
  W X Y Z       is flipped end-to-end and laid alongside its opposite.

In this 3-&-4-sided board, there are 15 edge cells which thus connect to their opposite cells via Projective connections as shown here...

   z_y_x_w
  z/A B C\w     Each of the original edge/corner cells "re-appears"
 v/D E F G\r    on the opposite side, in lower case letters.
q/H I J K L\m
q|M N O # P Q|m Each corner still has 5 neighbors.
l\R S T U V/h
 g\W X Y Z/d
  c~c~b~a~a

So on the original board, cell H is connected to D I N M Q V (in order). Whereas M is connected only to N R L Q H.

The whole collection of 21 hexagons and 6 pentagons makes up a "standard" tiling of the Projective Plane.

To play the game, "Projective Hex", one merely plays as at Hex, filling any one cell your own colour on your turn; and whoever makes a global loop of adjacent cells of their own colour, is the winner. And, as mentioned above, it is only possible for ONE colour to do so, and at least one of them must always do so, by the time all cells have been coloured. So complementary winning conditions, and equal tasking have both been achieved.

Example: here is a completed game, with both having played 7 moves, and the 2nd player (white) has won, despite his opening disadvantage.

   . X O
  . . X O
 . . O O .
. X O X . .
 X O X . .
  X O . .

The loop might be more visible if "ghost" edge cells are entered as well...

    ___o_x
   /. X O\x
  /. . X O\x
 /. . O O .\
<. X O X . .>
 \X O X . ./
 o\X O . ./
  o~o~x~~~

For actually playing the game, naturally, as always, the first player has an enormous advantage; a sure win, in fact, by the usual strategy stealing argument. But beyond the very smallest boards it is very hard to find.

This advantage can be left as is, giving the weaker player first move; or (say for more formal games), one of the usual equalizing methods can be used. Probably the simplest is the "cut-and-choose" method of 3-move equalization (mentioned on another thread recently), whereby one player plays 3 opening moves, black-white-black, then the other player chooses which colour to be. It is also conceivable that even 2-move or 1-move equalization would be suitable, as e.g. the corner cells are not quite so valuable as the central ones, so an opening move there might well be a losing one, but only just, making 1-move
equalization a viable option.

Play Hex in different boards

2007-03-16T12:41:00.000Z

[from here] Here are some alternate boards to play Hex on. This first one I call "Pex11" because the cells are all pentagons, and the tiling is number 11 on the list of all known classes of pentagon that tile the plane. The complete list can be found here (Check also the Penrose tilings).

Of all the classes given, only two of them, 11 and 14, meet these criteria:
* nowhere do more than three pentagons meet in a point.
* the pattern is topologically distinct from a hexagonal grid.

In a normal hex grid, each interior cell is adjacent to six other cells.
In the type 11 pattern, half the interior cells are adjacent to five neighbors.
and the other half are adjacent to seven. The pentagons are colored accordingly.

Chili Sandwich Chess

2007-03-16T09:27:00.000Z

1. The FIDE rules apply, except in the following.
2. Whenever a piece or pawn moves, all pieces and pawns between it and
another piece of the same type (on a row or column), are taken.
3. There is no FIDE capture.

Eg, Rg6 would take Be6 and pawn g5

. . . . . . . .
. . . . . . . .
. . r . b . . R
. . . . . . p .
. . . . . . . .
. . . . . . . .
. . . . . . R .
. . . . . . . .

variant 1: change "are taken" to "change color"
variant 2: change "are taken" to "change to color of player"
variant 3: change "type" for "color"
variant 4: add diagonal captures
variant 5: delete rule 3.

Delegating Chess

2007-03-16T09:24:00.000Z

1. Like FIDE Chess, except:
2. Non royal pieces move (capture) like one of the friendly pieces that can move (capture) to its square. In the case of Pawns, they give their diagonal forward capture to friendly pieces in the squares they could capture to, and their forward non-capturing move to a friendly piece right in front of them on the square they could otherwise move to.
3. There is no castling.
4. There is no Pawn double-move or en-passant capture.

Notes:

* A non royal piece which is not in the moving (capturing) range of another piece of the same color, cannot move (capture).
* The King moves and captures like the FIDE King.
* There is still Pawn promotion on last rank.

Sample



Q c . k . . .
p . . . . . .
. . n . . b .
. . . . . . .
. . . . . q .
. . . . . . N
. . . . . . .
. . . . . . .
. . . . . . p
. O . . . . .
. . . . . . .
R . C K . . Q

1. b3-e5+ (since Cc1 can move to b3, the pawn may move like the Cardinal)
1...  Nc10-d8 (to protect the King, he also could move like the Cardinal at b12)

Q c . k . . .
p . . . . . .
. . . . . b .
. . . . . . .
. . . n . q .
. . . . . . N
. . . . . . .
. . . . . . .
. . . O . . p
. . . . . . .
. . . . . . .
R . C K . . Q

2. Kd2 (freeing the Cardinal to move like the Queen at g1)
2...  Q:g7 (it also uses the power of Cb12)

Q c . k . . .
p . . . . . .
. . . . . b .
. . . . . . .
. . . n . . .
. . . . . . q
. . . . . . .
. . . . . . .
. . . O . . p
. . . . . . .
. . . K . . .
R . C . . . Q

3. d4:g4 (attacking the Queen at g7 with the power of Qg1)
3...  Qe9+ (the check is because of the Knight)

Q c . k . . .
p . . . . . .
. . . . . b .
. . . . q . .
. . . n . . .
. . . . . . .
. . . . . . .
. . . . . . .
. . . . . . O
. . . . . . .
. . . K . . .
R . C . . . Q

4. g4-e4
4...  C:a12 (capturing the useless Queen)

c . . k . . .
p . . . . . .
. . . . . b .
. . . . q . .
. . . n . . .
. . . . . . .
. . . . . . .
. . . . . . .
. . . O . . .
. . . . . . .
. . . K . . .
R . C . . . Q

5. Cc2 (giving Rook powers to the Queen, and C+Q powers to the Rook).
   and so on...

Clues for a Conceptual Toolbox for the Game Designer

2007-03-16T09:15:00.000Z

Abstract Games are very curious mathematical objects. They tend to be are deprived of any significant cultural context to present what – in principle – really matters to another curious thing called a game player. This act of cultural removal is rather subjective, but anybody can sense it, when we see several people around the world play the same game and enjoying it the same way. Many games, like Go or Chess are played on several dozens countries at this very moment. Not even conjectural prohibitions based on Religion, Law or by political reasons, manage to destroy the memory of the rules that define those persistent and rather illusionary things…

Here in, an abstract game is: (a) A game for 2 players; (b) with no luck element and no hidden information; (c) where each game turn (except perhaps the first and the last one) consists of a move by the 1st player and another by the 2nd player; and (d) the set of rules agreed by both players do not leave any space to ambiguity.

This, in a way, restricts the field of study, but leaves an endless Ocean of possibilities and magical wonders! We can say, with no hesitation, that Humanity only scratched the surface of such great Sea of Games. Herein, the goal is to present a set of conceptual tools for those who like to design and test new abstract games, to inform people how to avoid common errors and pitfalls and so, in conclusion, to create better games.

There are two concepts that I find most relevant! The first one is Depth, or strategic complexity, meaning the capability of a certain game to have a certain number of degrees of skillfulness. The exact number of different skills is never exactly known, even because no one reached an precise definition of what is a degree of skill. A possible way is to say that a player is one skill above the another if he wins 2 out of 3 games. Even saying that, skill levels of different players are not disjoint, since the concept is not transitive. Different ways of playing work better on certain players than others. Just like Soccer! The more skill levels a game has the better, it means that a person can continuously learn about the game for a long time (even more than a single life or an entire civilization). A deep game also gives the players more chances to recover from crises (i.e., bad moves), or stating differently, if a player on a relatively bad position is replaced by a better player, this one may still be able to balance the game.

The other condition is Clarity. Clarity means that most board positions should be as close as possible to the way the Human mind sees things. This concept will surely be very different for a Martian, but since no ET was found yet, let’s stick to this human-centered vision. Tic-Tac-Toe and Hex are exceptionally clear. There is not, however, a direct correlation between clarity and the description of the rule set. Some simple games to describe tend to mess a lot when an actual game is played, but a difficult game to describe will possibly have some clarity problems as well. For instance, many Chess Variant designers find on clarity a merciless judge. People are used to the way a Knight moves, but some similar fairy pieces (with the same right to existence as any other) create a problem of lack of clarity that prevents players to be interested on such opaque game.

The joint combination of this two features give a glimpse on the quality of the game. Tic Tac Toe suffers due to limited strategic possibilities, Go scores highly but is penalized by subtle rules, Hex scores very highly (I dare to say that 19x19 Hex would approach Go in depth, while retaining a much better clarity). A computational approach of this subject would say that given a game tree with N nodes, complexity would be the total nodes required to formulate sensible strategies, and clarity would be the ability to search deeply inside the game tree in order to achieve them.

Well, but this are just general concerns that you should have in mind. What about the real and objective game´s ruleset? The next section will talk about some basic game mutators. That is, modular concepts that can be applied to almost any game, creating new games (not necessarily better ones).

Basic Mutators

As we all found by experience, there are many good ideas out there hidden on obscure games. The next list is not intended to be complete, but it tries to dissect as many basic concepts as possible, in order to provoke people to mix them in some strange, new and hopefully also in skillful ways.

Let’s state some extra principles to those already stated on the initial Abstract Game definition. The game may have a board, consisting of cells linked together in some specific ways (a square tiling, an hexagonal tiling, a rhombus, …). Each player has, at least, one set of stones of a certain color (let’s say, black stones for the first player, white stones for the second), where the possible playing options are stated by the rules defining the game.

Each mutator must be seen as a rule, or part of a rule, that needs some preconditions before execution (i.e., may only works on certain game states/positions), and may create, when executed, events that enables other mutators to work (even on the same player´s turn). On the following list, some mutators have glimpses of possible preconditions and events.

Pass A player does not affect the game state. It is the null mutator.

Drop This is, probably, the most applied rule on abstract games. A piece may be dropped into a certain board cell. The drop restrictions can be various. The most common is that the cell must be empty. Other options would restrict it to a certain area (e.g., must enter into the players initial zone), on local conditions (e.g., must be near a friendly stone), or global ones (e.g., the board must not have more than x stones).

Move The move mutator is also very widely used. A stone already on the board, can move from a cell A to a cell B. This movement may be subject to certain restrictions, like intrinsic ones (e.g., it can just move to an adjacent cell, to orthogonal/diagonal cells, …), contextual ones (e.g., it can move to an empty cell, a cell not attacked by the opponent, only moves if it has x adjacent friends, …), or global ones (e.g., the total number of stones define how each stone can move).

Capture A set of stones, either friendly and/or unfriendly, are removed from the board and those cells become empty. This usually is an action caused by the execution of another mutator (most cases, this is a consequence of moving). Capturing can be a consequence of a certain pattern, like custodian capture (like Hasami Shogi), simple jumping (Checkers), cannon capturing (like in Xiang-Qi), bombing (all adjacent enemy stones are captured). Capturing may provoke several lateral effects, like Suicide (the captured piece is destroyed like in The Way of Go), or Protean capturing (the piece inherits the captured stones abilities, like in Cannibal Chess).

Jump A jump is simply using another stone to move to another cell not in range otherwise. This not include the Chess Knight, since it does not need another stone or piece to make its move.

Merge Two or more stones occupying the same cell are transformed into a different piece. Bashke, Laska and Focus use this concept in the Checkers game world.

Pivot The pivot mutator is a generalization of the Jump mutator. Usually a jump uses the intermediate stone as the pivot to move on a straight line. General pivot moves have much more liberty. Other kinds of pivot moving are scaling (check Scalus for use of that concept), and rotation (check Kefren or Twirls of Action) also known as Twirls, named by Claude Chaunier. These are just two possible ways to explore Pivot moves.

Swap A stone (the swapper) can swap position with another stone (the swapped). Possibly, the swapper will be on moving range from the swapped.

Shift Shift also means push a set of stones into a specific direction (e.g., check Epaminondas or Abalone). This shifting may produce other events, like single or group capturing.

Pile Piling inserts an extra dimension to bidimensional boards. There are several ways to pile, namely Staking (the new stone is placed on the top) and Queuing (is placed on the bottom).
This may provoke a change event, meaning that the new stone merged the piled piece. This also implies possibly a splitting mechanism.

Change This means changing the stone status. After the application of such mutator, a stone acts and reacts differently to the same conditions. Some examples include: stone promotion (increase its power) and demotion (decrease it), freezing (cannot move), stoning (cannot move or be captured), make royal/unroyal, …

Local Interactions After a move is done, the actual cell interacts it some local neighbors (the adjacent stones, the nearest orthogonal neighbors, …) and affects them. For instance, there are gravity forces (attracts all by one or more cells), and magnetic forces (attracts opposite color, repels equal ones). Some games where this is applied are Magnetic Go and Magnetic Chess.

Momentum A momentum mutator creates multi move games. It works like this: A previous moved stone will repeat its behavior on the following turns while it’s valid. Until now, from our knowledge, this was only used on Chess Variants.

Progressive This mutator affects the way turns are defined. The typical progressive mutator adds an extra movement for each player’s new move (one move for Black, two for White, three for Black, …). Other progressions are possible, softer ones (1, 2, 2, 3, 3, 4, 4, …) and wilder ones (1, 3, 5, 7, …). This obviously reduces the game length, and for some games it is a nice way to play a fast variant (give it a try with 9x9 Go). The set of movements could be sequential or simultaneous, it depends on the context where it is applied.

Save It’s a kind of active passing. The player gives the turn to the other player, but it saves the move for later use, i.e., next turn it can move twice in a row. This is a very strong mutator, and should be used with extra restrictions, in order to keep the game interest.

The produced events can activate more than one mutator. For example, a multiple move/capture is an application of a certain capture mutator within itself.

Improving the Spark

There is no magical formula for making an abstract game with depth and clarity. That implies a little of luck, insight or something else that creates the ‘spark’. I will speak of the something else, and also about the fact that the spark, if not treated right, may be lost, transformed into a poor game that lacked the basic care of any newborn.

Let’s start on the initial setup. First, the game designer should decide what shape will define the board and if it begins empty or not, if there is still the possibility to drop stones afterwards. A related point is to decide the total number of stones. A good rule is to see how stones are capable of moving (if they move at all). Board density (i.e., the average number of stones per cell) is relevant on this decision. A game with moving stones and growing density may face ‘traffic’ problems on the endgames. Usually if stone mobility is high, then density should be low, and vice versa.

If the designer chooses an initial setup, he must see if that setup does not go through another global pattern before the game really begins (i.e., both players found that to attack or defend, they should position their stones into a certain tactical pattern). In those cases, the designer should change the initial setup to that intermediate one. It will speed the initial phase, without decreasing its depth (this of course, may be risky, if the designer or the game testers are not able to see other potential good openings, on those cases, the game depth will suffer).

The number of moves of a typical game is an essential thing to note. Very short games are not very interesting, except for children, very long games take much time to be played and tend to be rather tedious. Perhaps if Go was presented today, it would suffer from this fate, many people would not be interested because it takes too long to finish a game, and they would miss its remarkable depth. Ralf Gering marks 20 turns (i.e., 20 moves for each player) has a minimal mark for a average game score, in order to have some interest. Of course, this also depends on the number of moving options, but too many options reduce clarity! This is a tight business! For maximal turns, an original game that takes more than 100–120 turns will need a good marketing!

An important subject is to avoid mirror tactics. This happens when one player can mimic the other, in order to achieve a draw (like in Halma) or even victory (like in Hip on even square boards). This can be done by using odd boards (that is with a center cell, usually called Tengen), allowing captures, or asymmetrical positions (i.e., that after a certain move, the other player cannot mimic it).

Two more things about the initial phase, Handicaps and Equalizers. Handicaps are always a good way for two players with different skills still manage to get some fun paying (ups, I mean playing) the game. This is done by creating a better position for the weaker player, by giving him some extra moves, extra material or easier winning goals.

Equalizing means to balance first (or even second) player’s advantage. This can be done, using an Handicap system; or by using the N-move equalizer: After N moves, the player on disadvantage may choose which side to play. When N is 2, this rule is also known has the PIE rule (i.e., you cut, I choose). There are other ways, like giving two moves per player, except for the first game move, but these are less general and may not work everywhere.

Besides the beginning, there is also the end! How the game should stop? What will be the winning goal? There are several classical concepts:

1. Territorial – wins the player with more controlled cells
2. Pattern – wins the player that first achieves a certain pattern of stones or cells: n-in-a-row, n-in-a-group, n-enclosed
3. Connecting – link two or more edges, link two or more special cells, link all friendly stones
4. Capturing – capture x enemy stones, capture some key stones (i.e., royal stones)
5. Reaching – reach a set of key cells, surround a certain stone or cell area

The designer should take special attention on one thing. On a typical endgame, the winning player has enough power to win? Is he able to decide the final outcome of the game? In Chess, we know that King + Bishop vs. King is a draw. If almost all Chess games would end on this position, then another winning rule would be needed (e.g., the Bare King rule – a player looses all other pieces are captured).

After the rule set is defined, the designer should look into each single rule and ask some questions: Is this rule necessary? Why is it so? Is it a logical consequence of some other rule(s)? If so, it should be placed on the notes section, not among the rules! Does the rule interacts with the other rules to create some more tactical possibilities? Or is it totally independent? If so, and if the rule decreases clarity without giving some to the game as an whole, then the designer should rethink about keeping the rule.

Combinatorial Game Theory talks about game temperature. A hot game state is one where the player has the advantage to move. Otherwise a cold game is one where the player does not want to move (in that sense, a game with a pass rule is never cold, since players may pass their turns). Some samples: Hex is hot and gets hotter. An extra move never hurts the player and usually puts them in a winning position, more so towards the end of the game. Go starts medium hot then cools down to lukewarm. Towards the end of the game moves become less effective until they are not worth making. Gonnect starts hot then suddenly turns freezing cold at the end. An extra move is good during the early and middle games, but can become a game-loser in the endgame. This does not give the designer a way to determine a level of quality, but can give him insights about how his own game reacts from the opening until the endgame.

Final Words

A really nice thought is to imagine that maybe some games invented in this century will be played in the year 3002 (perhaps one of your own games), where Hollywood, Microsoft, Intel, the Computer Game Industry, and so many other powerful businesses would already entered into oblivion…

PROGRESSIVE POKER

2007-03-16T09:09:00.001Z

With a normal deck of 52 cards:

Player 1 takes one card from the face-up deck, then player 2 takes 2,
then 3, then both players take 4 at a time till they have 25 each.

As soon as they are chosen, the player must add the cards as he chooses
to one of his 5 poker hands face-up on the table, (all starting empty).

When the 50 cards have all been played, all the poker hands are compared,
each against each, 25 comparisons in all.  Whoever records the greatest
number of wins, wins the game.

* Poker hands are in order:

Straight flush,
4 of a kind,    (i.e. same rank)
full house,     (a 3 of a kind and a pair)
flush,          (all same suit)
straight,       (5 in number sequence, A high or low but not both)
3 of a kind,
2 pairs,
1 pair,         (2 of same rank)
nothing.

Sample Game:



      Player-1                           Player-2
Ah.1                               As.2  Ks.2
Ad.3  Qs.2  Ac.4                   Js.1  2s.2  Kc.3  td.4
Kh.1  Qh.1  Jh.1  th.1             9d.4  8d.4  7d.4  6d.4
5h.3  5s.3  5d.3  5c.3             Qc.3  Jc.3  tc.3  9c.3
4c.5  4d.5  4h.5  4s.5             6s.5  7s.5  8s.5  3s.2
3h.2  3d.2  2s.4  ts.5             9s.2  3c.1  Qd.1  8c.1
 
Ah  Kh  Qh  Jh  th        1        Js  3c  Qd  8c  ..
Qs  3h  3d  ..  ..        2        As  Ks  3s  2s  9s
Ad  5h  5s  5d  5c        3        Kc  Qc  Jc  tc  9c
Ac  2c  ..  ..  ..        4        td  9d  8d  7d  6d
4c  4d  4h  4s  ts        5        6s  7s  8s  ..  ..

CARDS LEFT:

c : . . . . . . . 7 6 . . . .
d : . K . J . . . . . . . . 2
h : . . . . . 9 8 7 6 . . . 2
s : . . . . . . . . . . . . .

Cycle: a game that needs improvement

2007-03-16T09:00:00.000Z

[This is a bit of a challenge. The original rules follows but they do not provide a good dynamics, the game needs, if possible, improvement]

Played on a square board with orthogonal bridge connections.

On each turn, each player may:

1) Pass, or
2) Drop a friendly stone on an empty cell, or
3) Connect two orthogonally adjacent friendly colors with a bridge, or
4) Capture a stone in custodian capture (both friendly stones must have
been played in previous turns, so it takes a turn just to capture)
* A corner stone may be captured if both adjacent cells are occupied
by enemy stones
* KO rule - not the same board position in two consecutive turns.

After two consecutive passes, wins the player with the largest cycle
concerning friendly bridges.

Egs:

White has a cycle of size 4 (the smallest possible)
while black as a maximum cycle of size 12

.  .  .  .  .  .  .  .

.  .  o--o  .  .  .  .
      |  |
.  .  o--o  .  .  .  .

.  x  .  .  x--x--x  .
   |        |  |  |
.  x--x--x--x  x--x  .
      |        |
.  .  x--x--x--x  .  .

.  .  .  .  .  .  .  .

Capture, since it wastes a move, may not be executed
at once, leaving a lot of potential threats in the board

Should White capture the black stone or just continue to extend
his groups? If Black plays at d2 it forces the capture at d4
and gains one tempo sacrificing one stone (it should then play d1)

.  .  .  .  .  .  .  .

.  .  .  x  x  .  .  .

.  .  o--o  x  .  .  .
              
.  .  .  x  .  .  .  .

.  .  o  o  x  .  .  .

.  .  .  .  .  .  .  .

.  .  .  .  .  .  .  .

I'm not sure if it's easy to make larger cycles, so probably the game score
could be the sum of all the max cycles on each group (probably the sum
of the squares of all max cycle sizes - in order to players to take risks in
achieving larger cycles)

The game does not provide tactical richness and thus is dull. If you can work out a better variant, please send your proposal.

SLOWLY PROGRESSIVE ORTHODOX CHES

2007-03-16T08:56:00.000Z

Each player plays moves for both colours,
in series 1 3, 3 3, 5 5, 5 7, 7 7, 9...
Every move must be legal for an orthodox chess game

Sample Game



 1.   e4    * Nh6      
 2. * Ke2   * Na6      
 3.   Nc3     Nf5      
 4.   e:f5  * h5       
 5.   Qg4   * h:g4     
 6.   h3      Nb8      
 7.   h:g4    a6       
 8.   R:h8  * f6       
 9. * Rh6   * g:h6     
10. * Ke2   * Nc6      
11.   d3      h5
12.   g:h5    Bh6
13.   B:h6  * a4
14. * b4    * a:b
15. * Bc1   * R:a2
16. * Nb1   * R:a1
17.   Nc3     Ra2
18.   N:a2    Kf7
19.   N:b4    Qf8
20.   B:f8  * K:f8
21. * h6    * N:b4
22. * h7    * N:d3
23. * h8 N  * N:f2
24.   g4      Ke8
25.   g5      Kd8
26.   g6      Ke8
27.   g7      Kd8
28    g8Q++

Final Position

. . b k . . Q N
. p p p p . . .
. . . . . p . .
. . . . . O . .
. . . . . . . .
. . . . . . . .
. . O . K n . .
. . . . . B N .

This slower progressive sequence allows more strategy since mates are not so fast to achieve and, thus, tactical positions are possible to build and develop.

QUADREX

2007-03-16T08:03:00.000Z

Players alternately drop one of their own stones onto any empty cell.
If this results in the formation of a small square with two similar
diagonal stones and one opposite stone, then the 4th cell is immediately
filled by the pair's color. If this results in a similar situation,
the same applies again, and so on indefinitely. One move equaliser.

The winner is whoever completes an orthogonal own-path in his direction.

Sample Game:

a b c d e f g h i j k l m n o p        Horz  Vert
. . . . . . . . . . . . . . . .   1.   l8    i8
. . . . . . . . . . . . . . . .   2.   i11   g10
. . , . . . . x . o o o . , . .   3.   h9    g8
. . . x . . o . . o x o . . . .   4.   g4    k6
. . . . , o . x x x x x . . . .   5.   l4    k4
. . . . o . x . o x x . . . . .   6.   j4    l5+
. . . . . o o o o o . . . . . .   7.   k3++  d4
. . . . . o x . x . . o . x . .   8.   e6    h5
. . . . . . . o . . . . . . . .   9.   f5    h3
. . . . . . x x x . . . . o . .  10.   h7    g6
. . . . . . x x o . . . . . . .  11.   f13   h12
. . . . , o o x . . . , . . . .  12.   h14   h13
. . . . . o x x o . . . . . . .  13.   h15   h16
. . , . . . x o o . . . . , . .  14.   g12   g11+
. . . . . . . o . . . . . . . .  15.   i13+  g14+-
. . . . . . . x . . . . . . . .  16.   f8    i10+
a b c d e f g h i j k l m n o p  17.   g7+   j6
                                 18.   i6 !  i5+
                                 19.   j7+   n8
                                 20.   n10   resign

This is a new connection game with lots of potential, using a novel mechanism to prevent the expected deadlocks of connections in orthogonal boards.

QUADRAPHAGES

2007-03-16T07:54:00.000Z

In each turn a player
(a) moves his stones rookwise, the previous # of cells;
(b) announces a new number (between 1 and 8);
(c) moves his stones the new number of cells.

When a stone leaves a cell, it marks it with its own colour.
A stone may not land on a marked or occupied square, or leave the board.
Given a number, stone must move if it can, otherwise it remains stationary.
Intervening own-pieces or marks of either type do not block a move,
but opponent pieces do. The first move begins with operation (b) & (c) only.

The game stops when all four stones in succession fail to move; then...
the winner is whoever has the most marked cells.

              _XX_                         _OO_
1.  ....  ....     ....  ....    ....  ....  8  g9g1  c1c9 
2.  a7i7  i3a3  6  i7c7  a3g3    c9i9  g1a1  1  a1a2  i9h9
3.  g3f3  c7b7  6  f3f9  b7h7    a2g2  ----  1  h9h8  g2h2
4.  h7h6  f9f8  1  h6i6  f8g8    h2h3  h8h9  1  h3h4  ----
5.  g8g7  i6i5  3  i5i2  g7g4    h4h1  ----  6  h1b1  i8c8
6.  i2c2  g4a4  1  c2b2  a4b4    c8d8  ----  5  b1b6  d8d3

Current Position

a b c d e f g h i     
o o o . . . o o .  1  
o X x . . . o o x  2 
x . . O . x x o x  3 
x X . . . . x o .  4 
. . . . . . . . x  5 
. O . . . . . x x  6 
x x x . . . x x x  7 
. . o o . x x o o  8 
. . o . . x o o o  9

Playing @ Xiquilene, Moçambique

2007-03-07T12:24:00.000Z

1222 UNRESTRICTED 6-MOKU

2007-03-06T22:19:00.000Z

Wins the player that makes a 6 in-a-row on an unlimited square board.
Each player moves twice, except in the first move where just one stone is dropped

Sample game ('o' starts):

1. --- o24    o23 n24
2. m25 n25    l25 m26
3. n27 o26    p24 p25
4. o27 p27    q27 q28
5. n26 p28    l24 q29
6. o28 n29    'x' resigns

i j k l m n o p q r s t   
. . . . . . . . . . . . 20
. . . . . . . . . . . . 21
. . . . . . . . . . . . 22
. . . . . . x . . . . . 23
. . . x . x o x . . . . 24
. . . x o o . x . . . . 25
. . . . x o o . . . . . 26
. . . . . o o o x . . . 27
. . . . . . o o x . . . 28
. . . . . o . . x . . . 29
. . . . . . . . . . . . 30

Can you see why 'o' won the game?