Tsume Shogi Glossary: Key Terms Explained — Tsumero, Hisshi, Interposition, and More

When you read tsume shogi commentary you keep running into terms like tsumero, hisshi, and naka-ai. Once you know what they mean, the explanations become far easier to follow, so here is a glossary of the words that come up most often in tsume shogi and the shogi endgame. Browse to whatever term you need; each topic is explored in depth in the related columns at the bottom of the page.

Checkmate (tsumi)

The king is in check and, wherever it moves or whatever it interposes, it will be captured next move with no escape. When checkmate is reached the game is decided. Tsume shogi is the puzzle of finding the forced sequence that mates the enemy king in the fewest moves.

Check (ōte)

A move that threatens to capture the opponent's king next turn. The side in check must respond — by moving the king, capturing the checking piece, or interposing a piece in between. As a rule the attacker checks on every move to drive the king down.

Mate threat (tsumero)

A move that creates the state "if you do nothing, I mate you next turn." Also called a one-move threat (itte-suki). The opponent must defend or be mated, so stringing mate threats together is the essence of the endgame attack (yose).

Brinkmate (hisshi)

A mate threat that cannot be parried no matter how the defender responds. Because no defense works, mate is guaranteed on the attacker's next move. It is the completed form of the attack — one step short of checkmate — and is commonly studied as the step after tsume shogi.

Defense (uke)

A move that parries a check or a mate threat. In tsume shogi you read assuming the defender always answers with the most tenacious defense; only when every defense is exhausted can you call it mate.

Attacker and defender (semegata / gyokugata)

In tsume shogi the side that mates the king is the attacker (semegata); the side being checked and mated is the defender (gyokugata). Play proceeds as the attacker checks and the defender answers with the best defense.

Pieces in hand (mochigoma)

Captured pieces become your pieces in hand and can be dropped onto any empty square on your turn — a rule unique to shogi. In tsume shogi the attacker is given a set of pieces in hand as part of the problem, and how you use them is often the key to the solution.

Interposition (aigoma)

Placing a piece between the king and a distant checking piece (rook, bishop, or lance) to block the check. Breaking through the defender's interpositions is a major theme of tsume shogi.

Intermediate interposition (naka-ai)

An advanced defense that drops a piece on a middle square out of the checking piece's reach, against a distant check. It tries to throw off the attacker's reading and escape mate; spotting it separates stronger solvers.

Futile interposition (muda-ai)

An interposition that merely delays mate by one move with no real purpose. By convention it is not counted in a problem's solution. Recognizing "this is a futile interposition" keeps your reading clean.

Promotion (nari)

When a piece enters, moves within, or leaves the promotion zone (the opponent's first three ranks) it may be flipped to gain a stronger move. In tsume shogi the choice to promote, or to deliberately decline promotion (no-promote / narazu), can decide the solution.

Uchifuzume — illegal pawn-drop mate

Delivering checkmate by dropping a pawn from hand is illegal (uchifuzume). The same mate is legal if you advance a pawn already on the board (this is tsuki-fuzume, pawn-push mate). Sequences that avoid — or force the opponent into — this rule appear often in tsume shogi.

Sacrifice (sutegoma)

Deliberately dropping or moving a piece to a square where it will be captured. It is used to block the king's escape squares or to lure the king to a square where it can be mated — a hallmark tesuji of tsume shogi.

Escape route (tairo)

The king's escape squares. Tsume shogi works by closing off the king's escape routes one by one until it has nowhere left to flee.

Discovered check and double check (aki-ōte / ryō-ōte)

A discovered check occurs when your own piece moves out of the way, opening the line of a rook, bishop, or lance behind it so that that piece gives check. A double check is when one move gives check from two pieces at once; it cannot be answered by interposition (blocking one still leaves the other), so the only replies are to move the king or to have the king capture one of the checking pieces. Both are powerful mating tools.

Number of moves (tesū) — 3-move and 5-move mates

The number of plies until mate. Because the sequence ends with the attacker's checking move, a tsume shogi problem's length is always odd (1-, 3-, 5-move mate, and so on). Solving 3-move mates fluently is the first goal of improvement.

Cook, variation, false trail (yozume / henka / magire)

A cook (yozume) is an unintended extra solution that also mates. A variation (henka) is the branch when the defender chooses a different defense within the main line. A false trail (magire) is a first move that looks right but does not actually mate. TsumeDojo's problems are selected so the first move is unique and mate is reached in the shortest length.