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Drops · 持ち駒

Captured pieces come back.

In chess a captured piece leaves the game. In shogi it changes sides: it waits in your hand, and on any turn you may put it down on an empty square as your own move. Everything that makes shogi feel different follows from this one rule.

The rule

When you capture, the piece goes to your hand, (持ち駒), face up on the stand beside the board so both players can see it. On any later turn, instead of moving a piece on the board, you may drop one from your hand onto any empty square. That is your whole move. The dropped piece points your way and is unpromoted, whatever it was when captured: a promoted rook comes back as a plain rook.

A gold in hand can be dropped on any empty square their hand in hand
A gold in hand. Any empty square will do, and from the next move it moves like any gold on the board.

A drop cannot capture (the square must be empty) and cannot promote on arrival, even inside the promotion zone. It can give check, and it can block a check against you. From then on the piece is an ordinary piece: it moves, captures and promotes like the rest.

Four squares you may not use

1. No second pawn on a file

You may not drop a pawn onto a file where you already have an unpromoted pawn. A promoted pawn does not count, so once your pawn has become a tokin the file is open again. Over a real board this is the most common way to lose a game by illegal move, and for good reason: pawns are what you have most of in hand.

Nifu: a second pawn may not be dropped on the fifth file their hand in hand
Nifu. You already have a pawn on the fifth file, so the pawn in hand may not land anywhere on it.

2. Nowhere a piece could never move

A pawn or a lance may not be dropped on the last rank, and a knight may not be dropped on the last two: from there they would have no legal move for the rest of the game. Every other piece may be dropped on any empty square.

Dead drops: a pawn or lance on the last rank, a knight on the last two their hand in hand
Dead squares. The last rank is closed to a pawn or lance; the last two are closed to a knight. Dropped there, the piece could never move again.

3. No checkmate by dropping a pawn

You may not give checkmate by dropping a pawn. Dropping a pawn to give check is fine, and mating by moving a pawn one square forward is fine too; the rule is only about the drop that ends the game. It is old, it is odd, and it comes up more than you would think in the endgame, where a pawn in hand is often the last piece left to attack with.

Uchifuzume: dropping the pawn on 5b would be checkmate, so it is illegal their hand in hand
Not allowed. A pawn dropped on 5b would be mate: both silvers guard it and the lances block the king’s own escape. Because the mate comes from a dropped pawn, the move is illegal.
The same mate by moving a pawn is legal
Allowed. The same pawn already on the board steps to 5b: checkmate, and perfectly legal. The rule is about the drop, not the pawn.

4. Nothing that leaves your king in check

As with any move. A drop can block a check, and often that is the best way to answer one, but it cannot ignore one.

Why it changes everything

Try a drop.

The app’s lesson on drops hands you a gold and lets you put it anywhere. Then the bot will show you what a pawn in hand can do.

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