Four Player Shogi

Four Player Shogi

Four Player Shogi is a 4-player adaptation of standard Shogi designed by Michael Shipley in 1999. It is played on a cross-shaped board with a 9×9 central area and a 3×9 wing on each edge, giving 189 playable squares. The overall bounding box is 15×15 with the four 3×3 corner sections off the board.

Starting Position

Each player occupies one 3×9 wing and commands a standard Shogi army, facing inward toward the centre.

North and South wings (back rank, inner to outer): Lance · Knight · Silver · Gold · King · Gold · Silver · Knight · Lance (back rank) · Rook and Bishop on 2nd rank (North: Rook on b-file, Bishop on h-file; South: Bishop on b-file, Rook on h-file) · 9 Pawns on 3rd rank.

East and West wings: Same army as North/South, but with Rook and Bishop positions swapped relative to North/South. (East: Bishop left, Rook right; West: Rook left, Bishop right, reading outward.)

No pieces may move through the 3×3 void squares at the four corners of the bounding box.

Piece Movement

All pieces move as in standard Shogi:

• Pawn: one square forward
• Lance: any number of squares forward
• Knight: two squares forward + one square sideways (can jump)
• Silver General: one square diagonally or one square forward
• Gold General: one square orthogonally or one square diagonally forward
• Bishop: any number of squares diagonally
• Rook: any number of squares orthogonally
• King: one square in any direction

“Forward” is always toward the opponent’s side (inward toward the board centre, away from each player’s own wing).

Promotion

A player may promote a piece when it enters, moves within, or leaves any opponent’s 3×9 wing. A piece must promote if moved to a square from which it has no legal moves in unpromoted form.

Promoted movement follows standard Shogi:

• Pawn, Lance, Knight, Silver → move as Gold General
• Bishop → Dragon Horse (Bishop + one orthogonal step)
• Rook → Dragon King (Rook + one diagonal step)
• Gold General and King do not promote

Drops

Captured pieces may be dropped on any empty square in lieu of a move, with restrictions:

• Pieces are always dropped in their unpromoted state.
• A piece may not be dropped where it would have no legal moves (e.g., a Pawn cannot be dropped on the opponent’s back rank).
• A Pawn may not be dropped to give checkmate.
• A player may not have more than one unpromoted Pawn on the same file; therefore a player may never have more than 15 non-promoted Pawns on the board at once.
• Pieces captured by a teammate cannot be transferred — captured pieces belong only to the player who captured them.

Game Styles

Team-Orthogonal: North + South vs East + West. Turn order: North → East → South → West. Partners may not capture each other’s pieces. A team wins when both enemy Kings are in checkmate simultaneously.

Team-Diagonal: North + East vs South + West. Turn order: North → South → East → West. Otherwise identical to Team-Orthogonal.

Individual: Each player fights all three others. Turn order: North → East → South → West. A player who checkmates an enemy King may capture that King on their next turn — the captured King is removed from play. Remaining pieces of the eliminated player stay on the board until captured; captured pieces in the eliminated player’s hand are removed. The last player with a surviving King wins.

Alternative individual variant: Check is not announced and the King is treated as a normal piece that may be captured and dropped as an additional King. The game ends when one player possesses all four Kings.

Attribution

Designed by Michael Shipley, 1999. Rules documented from chessvariants.com/shogivariants.dir/fourplayer.html.