WHISTLING TRICOLEUR

* On each turn, a player must either move or capture.
* A move is any number of unoccupied spaces in a straight line.
A moved piece must end geometrically closer to at least one enemy piece.
* A capture is either
(a) by whistling: a piece moves as above, and any enemy piece of the
appropriate colour which was adjacent to the line of movement,
but not adjacent to the starting or finishing cell, is removed.
But only A takes B takes C takes A.
(b) by crushing: a piece adjacent to any enemy may capture and replace it.
* Capture is compulsory, but it is mover's choice among alternatives.
* A player loses when he has no pieces left.

abcdefghijklmnopqrstuvwxyzABC
1 . . . a c . . . 1
2 . . . . b . . . . 2
3 . . . . . . . . . . 3
4 A . . . . . . . . . C 4
5 B C . . . . . . . . A B 5
6 . . . . . . . . . . . . . 6
7 . . . . . . . . . . . . . . 7
8 . . . . . . . . . . . . . . . 8
9 . . . . . . . . . . . . . . 9
10 . . . . . . . . . . . . . 0
11 b a . . . . . . . . c b 1
12 c . . . . . . . . . a 2
13 . . . . . . . . . . 3
14 . . . . B . . . . 4
15 . . . C A . . . 5
abcdefghijklmnopqrstuvwxyzABC
This is one game with a scissor-rock-paper mechanism, where fights must be carefully balanced with pieces of different status in order to succeed.

[update May 2011] There is an older, 1990, game called Tanagra that uses a similar capture mechanism.

CHICKEN GOMOKU (yet another sample game)

Black must make a 5-in-a-row, White must prevent him.
Both players play black moves until one declares
to be black, simultaneously passing.
Then alternation as usual starting with white.

a b c d e f g h i 0. J: e5 f3 h9 B takes x
. . . . . . . . . 1. e4 d5 10. f3 b3
. . . o o x x . . 2. c5 d4 11. a3 h5
o x x x x o x . . 3. f6 d6 12. f5 h4
. . . x o o o x . 4. d7 g3 13. h6 RESIGN
. . o x x o x x . 5. f4 g2
. . . x o o . o . 6. e2 g5
. . . o . . . . . 7. g4 d3
. . . . . . . . . 8. d2 c3
. . . . . . . x . 9. e6 e3

CHICKEN-CHESS (a complete game)

Initially white has no king and two queens.
The goal is for white to capture the king, black to prevent this.
Otherwise FIDE rules; castling permitted whenever neither piece has moved.

All moves (alternating) go to black in the first phase.
Any player, may optionally, on his move, take the black army and pass.
Then the other player moves with White and regular play begins.

1. B starts: e5,Nf6,Bb4,0-0,B:d2,B:e1,B:f2,J takes black
2. Nf3    Re8
3. e4     N:e4
4. Qd5    Nd6
5. Bg5    Re7
6. B:e7   Q:e7
7. N:e5   Nc6
8. Ng4    Bb6
9  Bd3    Nb4
10. Qh5    N:d3
11. c:d3    h6            
12. Nc3     Qg5          
13. Q:g5    h:g5          
14. h4      g:h4          
15. R:h4    Bd4        
16. Rah1    f5        
17. Nd5     f:g4      
18. Rh8+    Kf7        
19. Rf1+    Bf6        
20. Re1     b5        
21. N:c7   Rb8  
22. Nd5    Nf5  
23. Re8    Bb7  
24. Rhf8+  Kg6  
25. Nf4+   Kg5
26. R:b8   Bc6
27. Ne2    B:b2
28. g3     Be5
29. Rbe8   Bd6
30. Rh8    N:g3
31. N:g3   B:g3
32. Rhg8   g6
33. Re3    Bf4
34. B resigns

. . . . . . R .
p . . p . . . .
. . b . . . p .
. p . . . . k .
. . . . . b p .
. . . O R . . .
O . . . . . . .
. . . . . . . .

Trabsact Sagme Diaries

Silence is gold, stillness is time [T.Sagme, Meditations]

Different kinds of rules

Not all rules of a game are equal. Some define the essence of the game (like the existence of a royal piece in chess), others are just adaptations in search of better dynamics and subtler positions (like the queen's move range).

Even in abstract games, I tend to favor very short rules, acknowledging the fact that some fixing may be needed to create a proper rule set. I prefer games that focus on one sort of interaction instead of several ones and exploit it elegant ways. Using this criterion, Hex should be the most simple and deep game there is. The case of Go comes near but... e.g., the KO rule is a kind of second-order rule. It is a needed fix for a nasty consequence of the capture rule and it would be hard to come up with a better replacement but, nonetheless, KO is not the essence of Go. KO also implies extra information besides the one in the board (like castling in chess players must have memory of previous moves or positions) which, personally, I find unaesthetic.

We may try to look to all the rules of a game and partition them into the following (arbitrary) classification. First-order rules are the essence of the game (and, possibly, are the criteria to define if a variant belongs to the family of the standard or 'essential' game). Second-order rules are those in order to make the game playable and its dynamics as enjoyable as possible. Rules like these, if well chosen, are a good pathway to create a fine abstract game (but, at this moment, starts a new business: make all those rules interact properly which is much more difficult than joining some unrelated good ideas in the same pot). There are also third-order rules: extra rules that provide little to nothing for the game essence except to contribute artificially to the game dynamics.

I would say, for FIDE chess, castling and e.p. are 3rd order rules. The piece movement of the FIDE army is 2nd order (remember Betza's different armies for other instances of chess soldiers) and also the one piece per turn move sequence (progressive variants still use the knowledge and instinct from chess experience). The concept of royal piece and capture by replacement would be first-order.

SAFE PROGRESSIVE CHESS

Standard progressive, but mate may not be given except against a bared king.

. . . . . . . .     |  1. Nf3
. p k . . p . p     |  2. Nc6 d5
. . . . . . . .     |  3. Ne5:c6:d8
. . . . . . . .     |  4. Be5:c2:d1 R:d8
. B . . . . . .     |  5. e4:d5 d6:c7:d8Q+
O . . O . . . .     |  6. K:d8 Be2:f1:g2:h1f3
. . . . . O . N     |  7. h456:7:h8Q:g8:f8+
. . . . K . . .     |  8. Kc7 a543:b2:a1Qh8:f8
____________________'  9. Ba3:e7:f8b4 a3 d3 Nd2:f3h2
                      10. resigns

In this variant, both players can focus on destroying the enemy army without concerning against premature mates (I'm not saying this is better, just that is different).

CHICKEN GOMOKU (another sample game)

Black must make a 5-in-a-row, White must prevent him.
Both players play black moves until one declares to be black, simultaneously passing.
Then alternation as usual starting with white.

a b c d e f g h i  0. B:  e5,h1,f2,h9  B takes black.
. . . . . . . x .  1. f4:J B:e3
. . . . o x o . .  2. d4     e4
. . x . x x . . .  3. e2     e6
. . . o x o . . .  4. e7     d5
. . . x x o . . .  5. f5     f3
. . x . x . . . .  6. g2     f7
. o . . o x . . .  7. g8     c6
. . . . . . o . .  8. b7     c3
. . . . . . . x .  9. resign 0-1

SUICIDE BOMBER CHESS

Same as FIDE chess except: Moves are only to empty squares, after which all opponent pieces kingwise adjacent to the new position are destroyed; and if there are any of those, the moving piece is also destroyed.  Win by killing the king, who may not suicide.

. r . . k . . .|  1. b4   h5    10. Ne2  Nf6   19. Rh1  Bh6
. . . . p . . .|  2. e3   b5:   11. a5   g6    20. Ng3  f6
. . . . . . . .|  3. Ba3  d6    12. a6:  Bg7   21. Nh5: Kf7
. . . O . . . .|  4. Nc3  Na6   13. d4   Qc1:  22. Rg1  Ke8
. . . . . . . .|  5. Nb5: Ba6   14. d5   O-O   23. Rg7: resigns
. . . . O . . .|  6. Bb5: Rb8   15. h4:  bh6
. . . . . . . .|  7. Bb4  c5:   16. g4   g5:    1-0
R . . . K . . .|  8. a4   Qc8   17. Rg1  Ng4
                  9. c4   d5:   18. f3:  Bg7

DIABALLEX

[rules]

abcdefghijklm       Bx                  Jo
   x x x .    1.  h1-f3            h7-i6  j7-h5^
  . J o . .   2.  f3-e4  d1-d5^^   g6-i4^ d7-h3
 . . . o o .  3.  j1-h1  e4-c6^    i6-i2  h5-f3
. . . . . . . 4.  h1-j1  g2-h1     i2-e2^^ h3-g2
 . x . . . .  5.  h1-d1  j1-h1     i4-j3  f3-h3
  B . . . .   6.  resign!
   . o . .    7

The position of J's soldiers can win, no matter what B moves. Can you see how?

WEAPON CHESS

FIDE chess moves but to empty cells only. Castling is legal if neither
piece has moved. Object of the game is to kill the enemy king.

First player makes one move, then players make series of two moves until a capture is made, whereupon the series become of length three until the next capture, then four and so on.

Captures may be made as a series of one move only. The first capture may be of either type, hand-grenade or machine-gun, (both of which make the maximum number of takes available for that particular move); and after that each player's capture types must alternate.

During a series of non-captures it is permissible to play a piece into a position where it could make either sort of capture but does not do so, at the mover's choice, (declaration of capture type unnecessary).

. . k r . . . r     |  1. e4
p p p . p . . p     |  2. Nf6:(mg)e4                  
. . . . . . p b     |  3. g4g5 Nc3
. . . : . q : .     |  4. g6:(g)g5                  
. . . . . . . .     |  5. d4d5 Qe2 Bg2
. . . . . : . .     |  6. Ne4:(mg)c3f2
O O : . . . B O     |  7. Qf3:(mg)e4f7
. . K . R . . .     |  8. d6 Be6 Nc6 Qd7 Bh6 O-O-O
____________________'  9. Bg5 0-0-0 Ne2g3f5 Rhe1
                      10. Ne5:(g)d5f5
                      11. Rd5:(g)de6e5
                      12. Qf5:(mg)d5g5c2f3
                      13. resigns

PAINT-GUN CHESS

1. The FIDE rules apply, except:
2. Captures by machine-gun or grenade, at mover's choice.
    (The capture type includes all multiple hits of the type.)
  2.1 Machine-gun captures all pieces that could be captured using FIDE rules
  2.2 Grenade captures all adjacent (kingwise) pieces at the destination square.
3. Capture REDUCES the capturing piece by a rank: Q>R>B>N>P
    Pawns that capture are also removed.
    Kings capture without reduction of power.


. . k . r . n r | 1. Nc3    g5
p p . p . p . p | 2. b4     Bg7
. . : . . . . . | 3. Nd5::  Ba2::::
. . . N . . . . | 4. Qc1::  Nc6:d5
. . . . . . . . | 5. h4:    Qh4:::
. . . . . . . . | 6. g3:    O-O-O
. . . O O . . . | 7. Bg2    Re8??
. . R . K . N . | 8. Bd5:   resigns


A master move

addendum: This is a game of Turkish Checkers.

Trabsact Sagme Diaries

Always look into the paths of defeat. [T.Sagme, Proverbs]

CHICKEN GOMOKU (a game sample)

Black must make a 5-in-a-row, White must prevent him.
Both players play black moves until one declares
to be black, simultaneously passing.
Then alternation as usual starting with white.

a b c d e f g h i J: d3,i7,a9,i9,c9,i1,J takes x
. . . . . . . . x 1. e4 d6
. . . . . . . . . 2. d4 f6
. . . x . . o . . 3. e7 e5
. . . o o x . . . 4. c6 c7
. . . . x x x . . 5. b8 f4
. . o x . x . . . 6. g3 f5
. . x . o o . . x 7. f7 g5!!
. o . . . . . . . 8.
x . x . . . . . x 9.

And, at this point, J wins in 5 moves. Can you see how? playing at h6,g6,g7,g8,g9/g4 (select the previous text to see the solution).

Black has more resources in this game now that he needn't worry about defending against white attacks.

ABANONDAS

Like Epaminondas but phalanxes may also make 1-step orthogonal/diagonal sideslips//orthogonal sidesteps, provided all target cells are empty. Diagonal phalanxes can only make orthogonal sideslips.

Game Sample:
a b c d e f g h i j k l
                                 ooo              xxx
. . o o o o o o . . . .   1.  g1.g2 - g4    l14.k15 - l12
. . . . . . . . . . . .   2.  g3.g4 - f3    l12.l13 - k11
. . . . . . . . . . . .   3.  f1.f4 - f3        j14 - k13
. . . . . . . . . . . .   4.  f3.f6 - e3    k11.k15 - j10
. . . . . . . . . . o .   5.  e2.e6 - d3    j10.j15 - j7
. . . . . . . . . x o .   6.  k1.h1 - f1     j7.j12 - i6
. . . . . . . . . x o .   7.  d2.d7 - c3     i6.i11 - i2:2
. . . . . . . . . x o .   8.  l2.j2 - i2:1  b14.c15 - a13
. . . . . . . . . x o .   9.  l1.k2 - i4:1    i5.i7 - i4:1
o . . . . . . . . x . .  10.  i2.j2 - k2      i3.i6 - j4
o . . . . . . . . . . .  11.  g1.h2 - j4:1    j5.j7 - j10
o . . . . . . . . . . .  12.     k2 - j1     j8.j10 - i9
o . . . . . . . . . . .  13.  j1.j4 - j5    i14.i15 - i12
x . . . . . . . . . . .  14.  c2.c8 - b3        b15 - c15
. . x x x x . . x x . .  15.  b2.b9 - a10    i9.i13 - j9
                         16.  a1.a10: a13:3 b14.h14 - a14
a b c d e f g h i j k l  17.  ...(capturing 6 times )  
                         23.  i4.j4         g15.h15 - j15
                         24.  j8.j4 - k9     j9.j13 - j6
                         25.  b1.f1 - g1     resigns

CHICKEN GOMOKU

Black must make a 5-in-a-row in a 9x9 square board, White must prevent him.
Both players play black moves until one declares to be black, simultaneously passing.
Then alternation as usual starting with white.

a b c d e f g h i       bill first
. . . . . . . . .  1.    d3,h8,a9, J takes black
. . o . x . . . .  2. B: d6    c4 :J
. . . x o x . . .  3.    b5    e4
. . x . x o . . .  4.    f4    f5
. o . x x x o x .  5.    c2    h7
. . . o x . o o .  6.    g6    h5
. . . . o o . x .  7.    h6    e5
. . . . . . . x .  8.    g5    e6
x . . . . . . . .  9.    e2    e3
                  10.    e7    d5    
                  11.    f7    f3

After f3, J wins in 2 moves (can you see how?)

CHICKEN CHESS

Initially white has no king and two queens.
The goal is for white to capture the king, black to prevent this.
Otherwise FIDE rules; castling permitted whenever neither piece has moved.

All moves (alternating) go to black in the first phase.
Any player, may optionally, on his move, take the black army and pass.
Then the other player moves with White and regular play begins.

Sample

1. e5,Nf6,Bb4,0-0,B;d2,B;e1,B;f2,J takes black
2. Nf3    Re8
3. e4     N;e4
4. Qd5    Nd6
5. Bg5    Re7
6. B;e7   Q;e7
7. N;e5   Nc6
8. Ng4    Bb6
9. Bd3    Nb4
10 Qh5    N;d3
11 c;d3   h6
12 Nc3    Qg5
13 Q;g5   h;g5
14 h4     g;h4
15 R;h4   Bd4

r . b . . . k .
p p p p . p p .
. . . n . . . .
. . . . . . . .
. . . b . . N R
. . N O . . . .
O O . . . . O .
R . . . . . . .

In this moment, Black tries to swap as many material as he can, so that White could not have enough force, at endgame, to checkmate the black King.

Trabsact Sagme Diaries

The rules of a game must be as simple as possible, not simpler. [T. Sagme, Conversations with Einstein]

SAS FENCES

Cul-de-sac with 2 piece-moves/turn, and L-shaped walls allowed. Each player has one grenade, which may be played at the start of a turn to blast an unfillable hole in any unit of wall; and this uses the placement power for that turn.

Here is a match where the South player (ie, which must go to the north edge) was forced to close himself.

       S           N                  S           N
1.  -N  EGd     SE  FHi        11. WN  Je4    gJKf SS
2.  NW  GId     EE  Ei4        12. WN  JLi    SW  Hik
3.  SW  Jc2     WS  Dj4        13. SN  Ii2    NW  Hh3
4.  SW  Ic3     WW  Ck4        14. SN  Hh2    EE  Fh4!
5.  EE  Fg4     EN  Fk3        15. resign
6.  WN  Gb4     EE  Iac        16.
7.  EE  Fik     NE  Gik        17.
8.  SE  Kbd     SS  Jc4        18.
9.  EN  JLf     SW  Ij3        19.
10  SE  HJe     ES  IKk

Final Position:

  A   B   C   D   E   F   G   H   I   J   K   L
a +-------------------------------------------+ a
  |                               |           |
b |   +   +   +   +   +   ,---+   |   +   +   | b
  |                       |       |   |   |   |
c |   +   +   +   +   ,---+   +---.---;---|   | c
  |                   |           |   |   |   |
d |   +   +   +   +-------+-------+   +   +   | d
  |                                           |
e |   +   +   +   +   +   +   +-------+---+   | e
  |                                   |       |
f |   +   +   +   +   +   +   +   +   >   <---| f
  |                                           |
g |   +   +   +   +   +   +   +   +   +   +   | g
  |                           |         N     |
h |   +   +   +   +   ,---+---+---+   +   +   | h
  |                   |       |   |           |
i |   +   +   +   ,---+-------+   +---+-------| i
  |               |   |   | S |               |
j |   +   +   ,---+   |   |   |---.   +   +   | j
  |           |       |   |   |   |           |
k |   +   .---+   +---.   +   +   +-------+   | k
  |       |           |                       |
l +-------------------------------------------+ l
  A   B   C   D   E   F   G   H   I   J   K   L

In this position, South only route of escape is between Ii and Li, since everything else has double walls and he has only one grenade.

WEITUWEIQI

Oshiqi mechanics with both players playing "x"s. Chicken start.
Moves are mandatory, and if the game ends by stalemate then the winner is determined by whether the boundary has been reached.
Any boundary hit is a win for ESCAPER, otherwise BLOCKER wins.
Hitting the boundary before either side has declared is an immediate loss.

Unlur or "chicken" starting:-  both sides play moves as if for the weaker side, in this case blocker.  If at any time a player feels blocker is now certain to win, he announces "I Block!", but does not make a move. The other player is thus escaper and plays the first move in regular alternation.

Note: If, still on the first phase, a player makes a stalemate position he loses (the other say 'I block' and he cannot continue)

                           bill  joao
abcdefghijklmnopqrstu      ----------
     . x . . . x        1. a6    n7
    x x . x x x .       2. m8    r3
   . . . . . . . x      3. k6    h1
  x . . . . . x . x     4. g2    b4
 x x . . . . x . . x    5. j7    e2,sw
x . . . . x . . . . .   6. b7,e  m2
 x . . . x . x x : x    7. i8,nw c4
  . . . x . x . . x     8. k2    p7
   x . . . . o . .      9. o2,sw e10
    x . . . . : .      10. n5    d9
     . . . . . x       11. s4    d5
abcdefghijklmnopqrstu  12. s8    p1
                       13. t7    o4
                       14. BLOCK t5
                       15. p11   resigns

This game uses a similar concept as in Unlur, which might imply a new family of games: "Chicken Games".

Slowly Progressive Chess

As Scottish progressive chess, but with the next move list:
1 2 2 3 4 4 5 6 6 7 8 8 ...

A game sample:

Q n . . . . . . | 1. e4
p . p k . . . p | 2. d5:e4
. . . . . . . . | 2. Nc3:e4
. . b . O . . . | 3. Bf4:d1 e5
. . . . . . . . | 4. d3 Bg5:d8 K:d1
. . . . . p . . | 4. K:d8 Nf6:e4:f2+
O O . . . . . O | 5. Ke2:f2 d4:e5 Nf3
R . . . . K r . | 6. g54:f3:g2:h1Q:f1+
                  6. K:f1 c456:b:a8Q
                  7. Kd7 Bc5 f543 Rg8g1++

The slower progressive step allows for more tactical positioning and a game with a better tempo (between progressive and FIDE chess). The move list was made to minimize the first player advantage (it is more fair than the typical 1,2,3... sequence).

Another variant, even slower, uses the following list: 1 2 2 2 3 4 4 4 5 6 6 6 7 8 8 8 (which is also quite fair, regarding first player advantage). Here two game samples:

. . . . k . . N  |  1. e4
p . p . p p p p  |  2. d5:e4
. . . . . . . .  |  2. Nc3:e4
. . . . . . . .  |  2. Bg4:d1
. . . . . . . .  |  3. Nc5:b:d8
. . . . . b n .  |  4. Be2:f1:g2:h1
O . n O . O . O  |  4. Ne6:f8g6:h8
. . B . K . N .  |  4. Nc6d4b3:h1
                    5. b4b5b6b7:a8Q+
                    6. B:a1f3 Nh6f5g3 N:c2++

. . . . . . . . | 1. e4
. . . . . . . p | 2. d5:e4
. k . . . . . . | 2. Bc4:f7+
. . . . p . . . | 2. K:f7 Nf6
. . . . . . . . | 3. d3:e4 Q:d8
. . . . . . . Q | 4. e5 Bc5 R:d8 b5
. O O . . . . . | 4. Be3:c5e7:d8
. . . . K . . N | 4. N:e4:f2:h1 Nc6
                  5. a4:b5 R:a7:a8:c8
                  6. N:d8 Kd7c7:b8 c6:b5
                  6. N,,:h1 Na3:b5a7+
                  6. Kb:a7b6 Ne6f4:g2+
                  7. h456:g7g8Q:g2 Qh3 & wins

DIABALLEX

On each turn, a player can (optionally) do the following, in order:
1: Make two Halma moves.  They must be with different pieces.
   Only one of these is allowed by the first player on the first move.
2: Swap the King with a soldier provided that they are
   in the same line and with no enemy piece directly between them.
   This may be repeated successively with several different pieces.
The King cannot move by any other means.
GOAL - Win by getting one's king into the last row.

abcdefghijklm
   o o o o    1
  . . B . .   2
 . . . . . .  3
. . . . . . . 4
 . . . . . .  5
  . . J . .   6
   x x x x    7
abcdefghijklm

Sample Game (notation: a1^ means king swaps with a1)

abcdefghijklm        Bo                  Jx

   . o . .    1.   ..   f1.h3       h7.i6  d7.f5
  . . o x .   2. h3.i4  j1.h7       j7.j3  f7.h5^
 . . o . x .  3. h1.f3  d1.f1       i6.i2  f5.g4^
. . . J . . . 4. i4.j5  ^j5h7  B wins
 . . . x o .  5
  . . x . .   6
   . . B .    7
abcdefghijklm

This game was inspired by Philippe Lefrançois's Diaballik

Trabsact Sagme Diaries

The roads of attack and the roads of defense seldom lead to the same destiny. Games not obeying this live at the razor's edge: they can be magnificent or broken. [T.Sagme, Meditations]

Election Games (4/4)

SEIRPINSKI COALITIONS

On each move fill a cell with your symbol; then (optionally): (a) move a piece from one large triangle to the corresponding empty cell on another, or (b) to the corresponding empty cell on a neighboring small triangle, or (c) to an adjacent empty cell in the same small triangle.

Two friendly cells in a small triangle win that triangle for the player.
Two won small triangles in the same large triangle win that for the player.
Two won large triangles for a player win the game.

Notation as in SEIRPINSKI ELECTIONS including ‘-’ to represent a move of type (a), ‘:’ a move of type (b), and ‘.’ a move of type (c)

Game sample:

      J’s           B’s  
   ========================
1.  111  -       222   -
2.  331  -       121  222-3
3.  231  -       333  322:3
4.  322  331:2   311  332:1
5.  123  322-1   132  121:3
6.  112  321:3   211  132-3
7.  233  331-2   resign

             j            
            j .            
                          
          .     b        
         j j   . .        
        ___________      
      b \         / b    
     . . \       / b .    
          \     /        
   j     j \   / .     -  
  . .   . j \ / . .   b b

So, this game mixes the election goal with a restricted move feature, so that players may reuse their dropped stones. The game converges to an end, since on every turn, a stone is dropped, and eventually the board is full. When that happens, there is always a winner.

Cubic

A very nice puzzle related to Sokoban. You drag stones horizontally, and when two or more of the same color are adjacent, they disappear. Gravity exists to pull your stones down.

Check http://www.agon.com/doodle/four.html and play online.