Alicechess is a chess variant invented in 1953 by V. R. Parton which employs two chessboards rather than one, and a slight alteration to the standard rules of chess. The game is named after the main character "Alice" in Lewis Carroll's workThrough the Looking-Glass, where transport through the mirror into an alternate 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.
Move rules
Pieces move the same as they do in standard chess, but a piece transfers at the completion of its move to the opposite board. This simple change has dramatic impact on gameplay. At the beginning of the game, pieces start in their normal positions on boardA, while board B starts empty. After each move is made on a given board, the moved piece is transferred to the corresponding square on the opposite board. 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. 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. After capture, the capturing piece transfers to the opposite board the same as 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... Bg1is possible, although a white pawn is on f2 on board A. A final stipulation applies specially to moves by the king: a king may not transfer to a vacant square on the opposite board, if this would put the king in check. Castling is largely regarded as permitted in Alice chess. The en passant rule is normally not used, but can be.
Early mates
Fool's mate
Several exist, one is: 1. e4 d5 2. Be2 dxe4 3. Bb5. At first glance, it might seem that Black can simply interpose a piece between White's bishop and his king to block the check. 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. Another form of fool's mate: 1. e4 d6 2. Bc4 Qxd2? 3. Bb5# And another: 1. e4 e5 2. Qh5 Nf6? 3. Qxe5#
Null or zero moves are permitted. A king cannot escape check with a zero move, and castling is denied if either king or rook have made a zero move. By John Ishkan.
O'Donohue chess
Alice chess rules, except that a move is permitted even though the square normally transferred to on the opposite board is occupied. By Michael O'Donohue.
Duo chess
Black starts out on board B; transfers are optional; non-pawn pieces may make zero moves ; a king is checked when an opposing piece sits on the king's zero square; mate must cover the king's ability to flee via a zero move. By Jed Stone. Parton also introduced a smaller, 8×4 version of Alice chess. He also observed that Alice chess can be played using three boards instead of two. Alice chess rules can be adopted by practically any other chess variant too, by simply doubling the number of gameboards in the variant and applying the piece transfer policy.
