Shogi (Japanese Chess)

Introduction:

• 2 players make alternate moves on a 9x9 board attempting to capture their
  opponent's King.
• Black moves first.
• The 3 ranks (rows) furthest from each player are their "promotion zone".
• Each player has 20 pieces in an even game and the pieces can be distinguished by the Black piece names being in upper-case and the White piece names in lower-case.

Moves:

• The King (K) can move to any adjacent space on a rank, file (column) or diagonal.
• The Gold General (G) is similar to the King, except it cannot move diagonally backwards.
• The Silver General (S) is also similar to the King, except it cannot move backwards on a file or sideways on a rank.
• The Pawn (P) can move 1 space forwards on a file.
• The Rook (R) can move any number of spaces on any rank or any file.
• The Bishop (B) can move any number of spaces on any diagonal.
• The Lance (L) can move any number of spaces forwards on a file.
• The Knight (N) can jump to either of the 2 spaces which are 2 spaces forward and 1 space left or right.
• The Rook, Bishop and Lance can move any number of spaces in the directions indicated, but may not jump over a piece.
• The Knight, Lance and Pawn can only move forwards.
• The Knight can jump over a piece to move.

Promotion:

• When pieces move partly or completely in their promotion zone they may or may not be promoted. Normally the piece name is prefixed by a "+".
• The promoted Lance (+L), Knight (+N), Silver (+S) and Pawn (+P) move like a Gold.
• The promoted Rook (+R) acquires the moves of a King plus a Rook.
• The promoted Bishop (+B) acquires the moves of a King plus a Bishop.
• The Gold and King cannot be promoted.
• If a piece is not promoted when it could have been, it can be promoted later if it moves in its promotion zone. When a piece has been promoted, it stays promoted unless that piece is captured, in which case it reverts to its unpromoted state.
• A Lance or Pawn reaching the last rank MUST be promoted, otherwise they could not make any more legal moves.
• A Knight reaching either of the last two ranks MUST be promoted.

Capture:

• A piece moves onto a space occupied by an opponent's piece and that piece is removed. The piece is placed in a storage area, "in hand".

Drops:

• A piece "in hand" may be used and dropped at any vacant space on the board instead of making a move, but please note that pieces are dropped in an unpromoted state, and MUST be able to make a legal move.
• Also a Pawn cannot be dropped on a file where there is an existing unpromoted Pawn, and a Pawn cannot Checkmate by a DROP.

Object of the game:

• The object of the game is to capture the opponent's King.
• When a King cannot avoid being captured, it is said to be "Checkmated" and the game is over.
• No stalemate can occur as it is legal for the King to move into "Check" (the King may be captured).
• Agreed draws are not allowed.
• A draw may occur if the same board position and the next player to move are repeated 4 times during a game.

Illegal moves:

• An illegal move results in the loss of the game, no matter when the illegal move has been discovered.

Western Notation:

When writing game scores the following notation is recommended:

• P : Pawn.
• L : Lance.
• N : Knight.
• S : Silver.
• G : Gold.
• K : King.
• R : Rook.
• B : Bishop.
• - : move.
• x : capture.
• * : drop.
• + before name : promoted piece.
• + after move : promotion.
• = after move : no promotion.

• S-3e : move Silver to file 3 and rank e.
• Gx5g : capture piece on file 5 and rank g with Gold.
• N-2b+ : move Knight to file 2 and rank b, and promote it.
• N-2c= : move Knight to file 2 and rank c, and do not promote it.
• L*5e : drop Lance on file 5 and rank e.
• +R-4h : move promoted Rook to file 4 and rank h.
• B5b-7d : move Bishop to file 7 and rank d from file 5 and rank b (to avoid ambiguity!).