Alice chess-The Daily Ledger

Alice chess is a chess variant invented in 1953 by V. R. Parton which employs two chessboards rather than one, and a slight (but significant) alteration to the standard rules of chess. The game is named after the main character "Alice" in Lewis Carroll's work Through the Looking-Glass, where transport through the mirror into an alternative world is portrayed on the chessboards by the after-move transfer of chess pieces between boards A and B.

This simple transfer rule is well known for causing disorientation and confusion in players new to the game, often leading to surprises and amusing mistakes as pieces "disappear" and "reappear" between boards, and pieces interposed to block attacks on one board are simply bypassed on the other. This "nothing is as it seems" experience probably accounts for Alice chess remaining Parton's most popular and successful variant among the numerous others he invented.

Alice chess

Move rules

At the beginning of the game, pieces start in their normal positions on board A, while board B starts empty. At each turn, a player can choose whether to move on board A or B. Pieces move the same as they do in standard chess, but, at the completion of its move, a piece goes "through the looking-glass", transferring to the corresponding square on the opposite board. This simple change has dramatic impact on gameplay.

Alice chess

For example, after the opening moves 1. Nf3 e6, the white knight and black pawn transfer after moving on board A to their corresponding squares on board B. If the game continued 2. Ne5 Bc5, the knight returns to board A and the bishop finishes on board B (see diagram).

Alice chess

A move in Alice chess has two basic stipulations: the move must be legal on the board on which it is played, and the square transferred to on the opposite board must be vacant. Consequently, a piece can capture only on the board upon which it currently stands; it then transfers to the opposite board, as for a non-capturing move.

To demonstrate, if the above game continued 3. Nxf7, the knight transfers to board B. Then with Black to move, both 3...Kxf7 and 3...Bxf2+ are not possible. Black cannot play 3...Qd4 either, since the queen may not hop over the pawn on d7. But the move 3... Bg1 is possible (see diagram), although a white pawn is on f2 on board A. (The bishop move on board B is legal, and the square transferred to, g1 on board A, is vacant.)

While making a move on the first board, the player is allowed to remain in check on the second board, if the transferred piece then interposes to block the check.

A player must not be in check on the first board after making the move but before the transfer; thus the king cannot transfer out of check.

A player must also not be in check on either board after the transfer; thus they must not put themself in discovered check on the first board by making the transfer, and the king cannot transfer into check on the second board.

Castling is largely regarded as permitted in Alice chess; both king and rook would then transfer to the second board.

The en passant capture is normally excluded, but it can be included. In most such games, the target square is considered to be the square passed over on the first board, though opinions differ.

Early mates

Fool's mate

Several exist; one is as follows: 1. e4 d5 2. Be2 dxe4 3. Bb5 (see diagram).

At first glance, it might seem that Black can simply interpose a piece between White's bishop and his king to block the check (for example, 3...Bd7 or 3...Nc6 or 3...c6). But any piece so interposed immediately "disappears" when it transfers to board B. And Black cannot escape check by fleeing to the opposite board via 3...Kd7, because the move is not a legal move on board A. Therefore, it is checkmate.