The board is a 6x6 board, extended in two sides by a unified 2x1 cell
each. The new cell at the bottom of the board is called 0,
while the one at the top of the board is called 7. These two
cells are linked by a big cell called X, such that pieces may
cycle from one side of the board to another.
+-------------------------------+
| X |
| +-------+ |
| 7 | | |
| +---+---+---+---+---+---+ |
| 6 |*R*|*B*|*Q*|*K*|*B*|*R*| |
| +---+---+---+---+---+---+ |
| 5 |*P*|*P*|*P*|*P*|*P*|*P*| |
| +---+---+---+---+---+---+ |
| 4 | | | | | | | |
| +---+---+---+---+---+---+ |
| 3 | | | | | | | |
| +---+---+---+---+---+---+ |
| 2 | P | P | P | P | P | P | |
| +---+---+---+---+---+---+ |
| 1 | R | B | Q | K | B | R | |
| +---+---+---+---+---+---+ |
| 0 | | |
| +-------+ |
| a b c d e f |
+-------------------------------+
There are thirty-nine cells in this variant:
There are 36 squares from a1 to f6.
The two cells 0 (covering both c0 and d0) and 7 (c7 and d7).
The cell X, which links 0 and 7 (described later).
Players start with the following pieces:
White rook a1, f1
White bishop b1, e1
White queen c1
White king d1
White pawn a2, b2, c2, d2, e2, f2
Black pawn a5, b5, c5, d5, e5, f5
Black king d6
Black queen c6
Black bishop b6, e6
Black rook a6, f6
Rules
Kings, queens, rooks, bishops, and pawns move as in normal chess, except:
There is no castling.
Pawns cannot double-step, and thus cannot be captured en-passant.
Pawns promote only to queen, rook, or bishop. There are no knights in
this game.
The special cells 0, 7, and X are linked as follows:
Kings must always remain on the 6x6 board. It may not move to cells 0,
7, or X.
Pawns must be promoted before they can ever make use of these special
cells.
Pieces that legally can move to the imaginary squares c0 or d0, can move
to cell 0.
To come out from cell 0 back to the board, they may either assume moving
from c0 or d0. They may not make a capture.
Pieces that legally can move to the imaginary squares c7 or d7, can move
to cell 7.
To come out from cell 7 back to the board, they may either assume moving
from c7 or d7. They may not make a capture.
Any piece in cell 0 or 7 may move to cell X. Any piece in cell X may
move to cell 0 or 7.
No piece may move from cell 0 to cell 7 or vice versa.
A special cell may be occupied only by one piece at a time. When a piece
is in a special cell, another friendly piece may not move into the cell.
An opposing piece may move into the cell, capturing the piece.
As noted above, pieces going out of cell 0 or 7 back to the board may
not make a capture. They do not give check either for obvious reasons.
The rule implies that bishops may change 'colors'. Hence, the board is
uncheckered.
Normal chess rules apply except when changed above.