Shogi promotion and drops: timing, double pawns and pawn-drop mate

The promotion zone covers three rows

Your promotion zone is the three rows nearest the opponent’s starting side. An unpromoted piece may promote when its starting square or destination lies in that zone. Moving into the zone, within it, or out of it can therefore offer promotion. Gold and king never promote.

Promoted pawns, lances, knights and silvers all move as golds. A promoted rook, the dragon, keeps its long horizontal and vertical moves and gains one-square diagonal moves. A promoted bishop, the horse, keeps its diagonal movement and gains one-square horizontal and vertical moves. A piece cannot voluntarily unpromote while remaining on the board.

Move a pawn from 5d to 5c

Assume the first player has an unpromoted pawn on 5d, 5c is empty, and it is that player’s turn. Both kings are outside the diagram. There is no current check, and moving this pawn does not expose its king. These conditions make the one-square forward move possible.

Next examine the destination. Row c is the third row of the first player’s promotion zone, so either promotion choice is available. If you promote, the pawn becomes a tokin on 5c and uses gold movement on a later turn. If you decline, it remains a pawn. This destination is not the final row, so declining is allowed.

Some moves require promotion

An unpromoted pawn or lance on its farthest row would have no future move. An unpromoted knight has no future move on either of its last two rows. Moves onto those rows must promote. Because a dropped piece cannot promote on arrival, drops of those pieces onto the same rows are prohibited.

Silvers and bishops can move backward, so this particular restriction does not force them to promote. A silver also loses its backward diagonal moves when it becomes a gold-moving piece. When both choices are available, consider which movement you will need rather than choosing solely because promotion is offered.

Drop an unpromoted piece on an empty square

A captured opposing piece joins your hand. Capturing a tokin gives you an ordinary pawn, not a promoted pawn. A drop places one piece from your hand on an empty square and consumes your turn. You cannot move another piece on that same turn. Dropping inside the promotion zone still places the piece unpromoted.

The double-pawn restriction concerns your unpromoted pawns in the same file, meaning the same column. If your pawn stands on 5f, you cannot drop another pawn on empty 5d. A tokin in that file does not count as an unpromoted pawn. An opponent’s pawn does not count toward your double-pawn restriction either.

A checking pawn drop is not always mate

Pawn-drop mate means dropping a pawn that immediately checkmates the opposing king. It is prohibited. A pawn drop that gives check is legal if the defender has a legal reply and all other conditions are satisfied. Giving mate by moving a pawn already on the board is not pawn-drop mate.

This site excludes double pawns, dead-rank drops, pawn-drop mate and moves leaving your own king checked. Forced promotion leaves only the promoted candidate; the choice dialog appears when both promotion and nonpromotion are legal. Select a piece in hand, then a destination. Before completing the move, check that the chosen piece and square match your intended idea.

Questions and answers

Can I promote as I drop into the enemy camp?

No. The piece arrives unpromoted. A later legal move involving the promotion zone may allow it to promote.

Does a tokin prevent another pawn drop in its file?

A tokin does not count toward double pawns. Another friendly unpromoted pawn in that file does, and all other drop restrictions still apply.