Hasami Shogi

Hasami Shogi

Hasami Shogi (はさみ将棋, “sandwiching chess”) is a distinct branch of the Shogi family with a single piece type, no drops, and no promotion. Capture is by sandwiching: a piece is removed when flanked on two opposite sides by the opponent. Ancient origin; public domain.

Setup

Board: 9×9 grid, 81 squares.

Pieces: 9 per player, all identical. Player 1 places 9 pieces on the nearest rank; Player 2 places 9 pieces on the far rank.

Rules

Movement: Pieces move orthogonally any number of empty squares, in any direction. This is the same range as a Rook in chess. A piece cannot jump over another piece.

Capture (custodial sandwich): A piece is captured when an opponent moves a piece to flank it on two opposite sides along a row or column. The moving piece must close the trap: moving between two opponents does not capture the mover. One move may sandwich and capture multiple pieces simultaneously if several are flanked at once.

Corner capture: A piece on a corner square is captured when both adjacent squares (one on the row, one on the column) are occupied by opponent pieces.

Self-protection: A player cannot lose their own pieces on their own turn. If a move sandwiches a friendly piece between two opponents, that friendly piece is not captured.

No drops. No promotion.

Win Condition

The player whose pieces are reduced to one remaining piece loses.

Attribution

Hasami Shogi (Variant 1). Public domain. Sources: steventran619/Hasami-Shogi implementation documentation; ryan-gallagher-atx/Hasami-Shogi-Game (OSU CS162 final project); OlliePoole/Hasami-Shogi iOS implementation.