Ripple Effect

[from Nikoli website]

The areas, divided by bold lines, are called "Rooms". Fill in all empty cells with numbers under following rules:

1. Each Room contains consecutive numbers starting from 1.
2. If a number is duplicated in a row or a column, the space between the duplicated numbers must be equal or larger than the value of the number.

Solution:

Nonogram (aka Paint By Numbers)

[from havards website]

1. Paint some black cells such that they obey all numbers:
   
2. Each number determines a number of consecutively filled squares (called a cluster).
3. Each number sequence (row or column) shows how many clusters are there and the cluster sequence (naturally, each cluster is separated by, at least, one empty cell).
   

Solution:

To read more, go to the Wikipedia entry. Also check a similar puzzle, Solitaire Battleship.

Black Cells

[from Nikoli website]

1. Place black cells according to the next rules:
2. Each number on the board represents the sum of white cells from that number to black cells or outer frame, horizontally and vertically.
3. The cells which include numbers are always white.
4. Black cells must not touch each other horizontally or vertically.
   
5. All white cells must be orthogonally connected.

Solution:

Tentai Show

[from Nikoli website]

1. Draw a bold line over the dotted line and divide the board into blocks.
2. Every block must have horizontal and vertical symmetries with a star at its center.

Solution:

Number Link

[from Nikoli website]

1. Connect same numbers with continuous line.
2. Lines must go through the center of a cell horizontally or vertically and never go through twice the same cell.
3. Lines cannot be crossed, branch off or go through number's cells.

Solution:

Divide by Box

[from Nikoli website]

1. Divide the grid into rectangles.
2. Each rectangle contains only one number.
3. The number indicates how many cells are contained in the rectangle.

Solution:

Heyawake

[from Nikoli website]

The rectangle, divided by bold lines, is called "Room". Each number indicates how many painted cells exist in its room, while no number rooms may have any number of painted cells. Paint cells under following rules:

1. White cells must not exceed two rooms in a straight line.
2. The painted cells must not be orthogonally connected.
   
3. White cells must not be (orthogonally) separated by painted cells.

Solution:

Nuruomino (aka LITS)

[from Wikipedia]

1. Shade a tetromino on each area, such that:
2. Every pair of orthogonally adjacent tetrominoes are not equal (considering rotations and reflections),
3. The shaded cells are all orthogonally contiguous and contain no 2×2 square tetrominoes as subsets.

Solution:

DIAMOND & PIVOTS (v.2)

1. On each turn, each player passes or drops a stone on an empty cell.
   There is a swap option after the first half-turn.
2. If any diamond patterns with four friendly stones are made, the player
   must choose one, choose a stone from it (the pivot), and place
   its other three stones in a line starting from the pivot.
  2.1 Every stone (of either color) that was on those destination cells
      are captured and removed from the board.
  2.2 If, after a pivot movement, another diamond shape is made,
      the player must repeat this procedure.
3. A stone may not be played to make a group of more than four stones,
   unless it thereby makes a diamond.
4. After two consecutive passes, wins the player with more
   stones (if equal, wins the 2nd)

Sample game:
abcdefghijklmnopq
    . . . . .      1.  c7 <--pied  i5
   . . . . . .     2.  d6          j4
  . . . . x x .    3.  e7          k5
 . . o x o x . .   4.  h4          m5
. . x x . x o . .  5.  l4        j6,h4-n4::
 o o x o . . . .   6.  h6     k5,k5-e5,h4-e7:
  o x . . . . .    7.  f4          l4
   . . . . . .     8.  m5          k3
    . . . . .      9.  j4          m3
abcdefghijklmnopq 10.  b6

And then...

abcdefghijklmnopq
    . . . . .      1.  c7 <--pied  i5
   . . . . . .     2.  d6          j4
  . . . . x . .    3.  e7          k5
 . . o . x . . .   4.  h4          m5
. . . . x x x x .  5.  l4        j6,h4-n4::
 x x x x . . . .   6.  h6     k5,k5-e5,h4-e7:
  o x . . . . .    7.  f4          l4
   . . . . . .     8.  m5          k3
    . . . . .      9.  j4          m3
abcdefghijklmnopq 10.  b6

10...   l2,k3-h6::,h4k5,i5-o5:,e5i6,h6-b6::

First player resigns.


Nurikabe

[from nikoli website]

1. You cannot fill the cells containing numbers.
2. A number tells the number of continuous white cells. Each area of white cells contains only one number in it and areas are separated by black cells.
3. The black cells are linked to be an orthogonally continuous wall.
4. Black cells cannot be linked to be 2x2 square or larger.

Solution:

Filomino

[from nikoli website]

1. Fill in all empty cells with numbers under the following rules:
2. The area, connected by the same numbers horizontally or vertically, is called "Block". Separate the entire board by Blocks.
3. Each Block contains as many cells as the number it contains (e.g., a Block of 6 has 6 cells).
4. Blocks of the same size must not touch each other, horizontally or vertically.

Solution:

Hitori

[from nikoli website]

1. Paint enough cell numbers such that:
   
2. No number may appear more than once in each row and each column.
3. The painted cells must not be orthogonally connected.
4. Un-painted cells must not be orthogonally separated by painted cells.

Solution:

Akari

[from nikoli website]

1. Place circles according to the following rules.
2. Circles are permitted at any white squares. Each number indicates how many circles are next to it, vertically and horizontally.
3. Each circle 'illuminates' from it to black square or outer frame in its row and column.
4. Every white square must be illuminated and every circle should not illuminate each other.
   

Solution:
It's possible to play online at http://www.puzzle-loop.com/

Hashiwokakero

[from nikoli website]

1. The number of connections is the same as the number inside the node
   
2. There can be up to two connections between two nodes
3. Connections cannot cross nodes or other connections
4. There is a continuous path connecting all nodes

Solution:
It's possible to play online at http://www.puzzle-loop.com/

Slitherlink

[from nikoli website]

1. Connect dots with vertical / horizontal line and make one loop.
2. Numbers are the hints to know how many lines can be drawn around it.
   There may be any number of lines around cells without number.
3. Lines cannot be crossed or branch off.

Solution:
It's possible to play online at http://www.puzzle-loop.com/

Masyu

[from nikoli website]

1. Make a single loop. Lines must pass through the centers of cells horizontally or vertically and never cross, branch off, or go through the same cells twice.
2. Lines must pass through all cells containing black and white circles.
3. Lines passing through a white circle cell must go straight through the cell, then make a right-angled turn in the very next cell (on at least one side of the white circle cell).
4. Lines passing through a black circle cell must make a right angled turn immediately, in the black circle cell, then go straight for the next two cells.

Solution:

Futoshiki

A new Japanese puzzle. As in Soduku, you must place all numbers from 1 to 5 in each row and column without repetition, but you must also satisfy the less than/greater than signals.

SLOW PROGRESSIVE GO 9x9

This game uses a progressive mutator in order to increase the dynamics of the original game. However, unrestricted Go drops would kill the game so two restrictions are added: (a) each stone on a drop sequence cannot belong to the same group (b) an atari stops the sequence.

Here's an example at a 9x9 board (white won 41-40). Herein it is used the slow progressive (1222344456667...)

a b c d e f g h i
. . . o x . . . . 1: c7
. . . o x . . . . 2: g3 g6
. . o o x . x x . 3: c3 e8
. . o x . . . . . 4: e2 g8
. . . o x . . . . 5: d2 d5 e7
. . . . o x x . . 6: d4 e3 e5 f7
. . o . o x . . . 7: d1 c4 e6 f9
. . . . o o x . . 8: e1 f6 g9 h3
. . . . . o x . . 9: d3 f8
a b c d e f g h i

HYDRA CHESS

Rules:

  1. Basic chess rules apply, except:
  2. When a piece makes a capture, it reduces rank and buds off
     a piece one rank lower, leaving this behind on the exit square.
     Ranks: KQRBNP-.

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

The Hydra game is a one-person game.

You start with a rooted tree, and at any move, you may remove one
leaf, and then duplicate (later triplicate, quadruplicate etc)
the whole remaining subtree it leaves, right down to the root.
The "n" in the n-plicate goes up one on every move, starting at 2.

                    *   *                         * *   * *
                     \ /                           \|   |/
So e.g. if we     *   *   *  ...it goes             *   *   *
delete the left    \ /   /      to this one,         \  |  /
leaf from this      *   *       when n=2.             * * *
tree...              \ /                               \|/
                      R                                 R

The number of nodes increases dramatically every time, but... the theorem is, no matter what you start with, and how you choose your leaf cuttings, IT WILL ALWAYS REDUCE to the empty tree, eventually !!

In fact, you don't even have to restrict yourself to increasing the n by one every time, you can up it in squares or powers of two or anything you like!

And it's one of those things that can be easily stated in basic number theory, (PA), but not proved there.  To prove it requires knowing about infinite ordinal numbers up to epsilon_0, if that means anything to you, which is the first ordinal that PA "can't handle".  i.e. can't prove that it is an ordinal, i.e. that
the above process must halt, (as it executes a decreasing series of ordinals, which therefore must always terminate).

You can see how the newly proposed budding chess emulates this slightly; there is an increasing number of pieces, but the total metric (in an appropriate sense) is always decreasing... i.e. the "top value".

Trabsact Sagme Diaries

The abstract game's fog should be adequate to the player's myopia [T.Sagme, Proverbs]

MONOCHROMATIC WHISTLING

MONOCHROMATIC WHISTLING

* 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 pieces
     which were adjacent to the line of movement, but not adjacent
     to the starting or finishing cell, are removed.
     Captures of this sort may be chained together (checkerswise).
 (b) by crushing: a piece adjacent to any enemy may capture and replace it.
* Capture is compulsory, with mandatory maximum capture (otherwise free).
* A player loses when he has no pieces left.
* After 20 consecutive non-capturing moves by each player, it is a draw.

Game Sample
    == XXX ==       == OOO ==
 1. s1-q1            h8-L8
 2. q1-i9:-c9: (f)   L8-C16:2-o1:2 (f)
 3. t2-l2:o1         g7-c11:c9
 4. i15-c9:c11 (f)   h6-b12:c9
 5. l2-e9:f6e7       x20-B20
 6. g15-b10:b12(f)   B20-M9:3  
 7. J15-M13          M9-N10
 8. v2-z2            N10-I15:M13-e15:2
 9. z2-L14:2         e15:f16 (f)
10. g17:f16          I7-M11
11. u1-A1            M11-G17::-r2:-D2:
12. resign

,'"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNO
1            . . . . . . . . : . .          
2           . . . . , . . . . . o .          
3          . . . . . . : . . . . . .          
4         . . . . . . . . . . . . . .          
5        . . . . . . . . . . . . . o o          
6       . . . . . . . . . . . . . . o o          
7      . . . . . . . . . . . . . . . . .          
8     . . . . . . . . . . . . . . . . . .          
9    x x . . . . . . . . . . . . . . . . .          
10  x . . . . . . . . . . . . . . . . . . .          
11 . . . . . . . . . . . . . . . . . . . , .
12  . . . . . . . . . . . . . . . . . . . .          
13   . . . . . . . . . . . . . . . . . . .          
14    . . . . . . . . . . . . . . . . . :          
15     . . . . . . . . . . . . . . . . .          
16      x . . . . . . . . . . . . . . :          
17       . x . . . . . . . . . . . , .          
18        . . . . . . . . . . . . . .          
19         . . . . . . o o . . . . .          
20          . . . . . o o . . . . .                    
21           . . . . . o o . . . .                      
`-.abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNO

This is a game of sacrifices to obtain larger captures. There are two ways of capture, but the whistling mecanism is a novel idea due to Bill Taylor.

SAFE CHESS (another sample game)

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

Game sample:
. . . . . . . .  |  1. Nf3
. . . . p . . .  |  2. f5 Nf6
. . b k . p . .  |  3. N,:d8
. . . . . . . .  |  4. f4f3:e2:d1Q+
p . . . . . . .  |  5. K:d1 Ne6:f8:d7:f6+  
. . . . . . . .  |  6. g:f6 Rg8:g2:h2:h1:f1+
. . O . . O . .  |  7. Ke2:f1 a456:b:c8Q+
. . K . . . . .  |  8. Kf7 Nc6 R:c8b8:b2:b1:a1:c1+
                    9. Ke2 d456:c78Q:c6 Kd2:c1
                   10. h5h4h3h2h1B:c6 Ke6d6 a5a4

DESTROY AND BUD

1. Basic chess rules apply, except:
2. When a piece makes a capture, it buds off a piece one rank lower,
   leaving this behind on the exit square.  Ranks  KQRBNP-.

Game Sample:
                        
r . b . k . n r     |  1. e4    e5         10. Kg1  Rh:h2
p p p p . p p p     |  2. d4    Nc6        11. R:h2 Q:g3+
. . B . . . . .     |  3. d:e5  Bc5        12. resign!
. N n . r . . .     |  4. Bb5   B:f2
. . . . . . . b     |  5. K:f2  Qh4+
. . . . . O q .     |  6. g2    Q:e4    
O O O . r . . R     |  7. Nf3   N:e5  
R N B Q . . K B     |  8. N:e5  Q:e5  
                       9. B:c6  Re2+

As people can see in the game sample, the ploriferation of pieces allow for strong and dealy attacks against the adversary force. Since there is a demotion mechanism on the captures, the game converges to an end.

SPARTAN CHESS

Rules of FIDE chess, except:
Start with 30 pawns and 2 kings each (at d1e1/d8e8)
Goal: capture both opponent kings.

1222... progressive mutator. The two moves in a turn must be made with different pieces.
If one king is captured, the victim goes down to 1 move per turn.
Pawns may move 2 steps off 1st or 2nd row at any time, e.p. applies.
Whenever a piece makes a capture, it goes UP a step in power,
using the sequence P>N>B>R>Q>A(=QN). 8th-rank pawns promote to A.

Game sample:
                       White        Black
p . p k k p . p  1.  ---  d:e5   d:e5  g:f4
. p p p p p . .  2.  e:f4 e:d5   e:d5  N:d3
. . . . . p . b  3.  g:h5 a:b5   a:b5  g:h5
. . N . . p p .  4.  b:c5 c:d3   b:c5  n:f4
. n n . . O . .  5.  N:f4 c:d5   c:d4  h5  
. O K O O O O O  6.  a4   c4     N:f4  Nd4
. . . . . . . O  7.  g:f4 e3     N:a4  N:b3  
. . O . K O O O  8.  a:b3 N:h5   B:b3  g6
---------------- 9.  B:g6 a2     h:g6  Rb6
                10.  c3   f4     N:h4  a4
                11.  b:a4 Kc2    Rb4  Bg5
                12.  b3   g3     Bh6  b5
                13.  Nc5  d3     b7   g6  
                14.  a3   f3     a5   g5
                15.  a:b4 Kc3    a:b4 b:c4
This is a very enjoyable game, with lots of capturing action starting at turn 1, and then shifting to subtle positional battles in order to promote to Amazons (Queen + Knight power). The fact that each player has two Kings also add an extra complexity of trying to protect both for as long as possible.

FRAGILE WEAPON CHESS

  1. The FIDE rules apply, except:
  2. Captures by machine-gun or grenade, at mover's choice.
     (A moving piece need not make captures that are available, but any made must include all multiple hits of that type.)
     Machine gun means capturing all pieces on capture range without moving and grenade means capturing all adjacent pieces after the piece move.
  3. Capture REDUCES the capturing piece by a rank: Q>R>B>N>P
     Pawns that capture are thus removed.
     Kings capture without reduction of power.
  4. Win by killing king.
  5. Castling legal when pieces have not moved.

r . . . k . n r     |  1. e4     d5:
p p p . p p . p     |  2. Bd3    g6
. . n . . . . .     |  3. b4     Bg7
. . . . . . . .     |  4. c3     Bg4:
. . . . . . . .     |  5. Bf5::  Qd3::::
. . . . . . . .     |  6. Bd2:   Bc3:::
O . . K . O O O     |  7. Kd2:   Nc6
. . . . . . N R     |  8. resign