Tsume Shogi for Beginners: How to Start With Mate in 3

Tsume shogi (詰将棋) is the checkmate puzzle of Japanese chess. You are given a position, a few pieces in hand, and a number. Your job is to mate the king in exactly that many moves. Shogi players have trained their endgame this way for centuries, and it is still the most common advice given to beginners who want to get stronger.

When I built Shogi365, I had to write every rule of tsume shogi into code, because the app lets you play the moves out on the board instead of looking up the answer. There is nothing like programming a rule to find out exactly what it says. This post is what I would tell someone starting today: the rules that surprise newcomers, how to read a mate in 3, and how to practise.

The rules, including the ones people miss

The basic idea fits in one sentence, but a few details decide whether your answer is actually correct.

Every attacking move must be check. You play as the attacker (攻め方), and every one of your moves must give check (王手). A quiet move that sets up a mate next turn is not allowed, however strong it would be in a real game.

Mate in exactly N, counting every move. 3手詰 means three moves in total: your check, the defender’s reply, your mate. Shogi counts each side’s move separately, so a mate in 3 is what chess players would call mate in 2. This is why the numbers are always odd. You move first and you move last.

The defender plays the best defence. The defending side (玉方) can make any legal reply: move the king, capture the checking piece, or block. Among those, it chooses the one that lasts longest. Your line only counts if it mates against every reply.

The defender holds all the remaining pieces. This is the rule that surprises people most. Every piece that is not on the board and not in your hand belongs to the defender, ready to be dropped in the way of a check. It is called 残り駒全部, “all the remaining pieces”. So a long-range check from a rook or bishop can usually be blocked with a drop, and you have to consider that.

Drop pawn mate is illegal. You may not give checkmate by dropping a pawn from your hand. This is 打ち歩詰め. Mating by pushing a pawn that is already on the board is fine. Puzzles sometimes use this rule on purpose, so that the obvious pawn drop is exactly the move you cannot play.

Two pawns on one file is illegal. You may not drop a pawn on a file where you already have an unpromoted pawn. This is 二歩, and it applies to the defender too.

Pieces that could never move again must promote. A pawn or lance on the last rank, or a knight on the last two ranks, has to promote.

Pointless blocks do not count. If the defender drops a piece in the way and you simply capture it and mate the same way, that block is called 無駄合い and is not counted in the length. In Shogi365 I went one step further: the puzzle generator rejects any main line that contains one, so the length on the screen is the length you actually play.

There is also a convention worth knowing. In a well-made problem every piece has a job, and the pieces in your hand are normally all used by the end. Every puzzle in Shogi365 was checked for this: each attacking piece, on the board and in hand, and each defending piece is necessary. So if your solution leaves a piece in hand unused, it is worth asking whether you missed something.

Why mate in 3 is the right place to start

A mate in 3 is short enough to hold completely in your head. You make one check, the defender makes one reply, and you mate. That means you can actually list every possibility, which is the skill everything else is built on.

It is also the length where the basic shapes of mate appear again and again. The simplest is 頭金, “gold on the head”. If the defending king is on 5一 with nothing around it, and you have a pawn on 5三, dropping a gold on 5二 is mate. The gold covers every square the king could go to, and the pawn protects the gold, so the king cannot take it. A great many mates in 3 are a single clever check that forces the king into a shape like that.

How to read a mate in 3

This is the order I would suggest. It sounds slow. After a few dozen puzzles it becomes quick.

1. Look at the king first. Which squares can it move to right now? Which of them are already covered by your pieces? The empty escape squares tell you what your checks need to take away.
2. List every check. Moves of pieces on the board and drops from your hand. In a mate in 3 there are usually not many, and writing them down in your head keeps you from fixing on the first one you see.
3. For each check, list every reply. King moves, captures, and blocks with any piece the defender holds. This is where beginners go wrong most often, because they forget the defender can drop things.
4. For each reply, find a mate. If even one reply escapes, the check is wrong. Move on to the next.
5. Give the strange moves a fair chance. Composers like first moves that look wrong: a sacrifice (捨て駒) the king can capture, a check that seems to push the king away. If every natural check fails, the answer is probably one of these.

Two old shogi sayings help here. 「玉は下段に落とせ」 says to drive the king down to the edge, where it has fewer squares. 「玉は包むように寄せよ」 says to approach it as if wrapping it up, not chasing it. Chasing a king up the board is how a mate turns into an escape.

How to practise

Read to the end before you touch anything. In a book you cannot cheat by moving pieces, which is part of why books work. On a phone it is tempting to try a check and see what happens. My suggestion is to decide on the whole line first, including the defender’s reply, and then play it to confirm. Shogi365 lets you play any check, right or wrong, and the king answers on its own, so a wrong idea fails on the board. That is useful feedback, but only if you had an idea before you moved.

Take a small hint before the whole answer. When you are stuck, seeing only the first piece to move is usually enough to restart your reading. In Shogi365 a hint lights up the piece and its destination, and you still make the move yourself.

Solve many easy ones. Most of the value in mate in 3 comes from volume. You are building a library of shapes, and the library grows by seeing them many times. A few puzzles every day does more than an occasional long session.

Move up when it feels like recognition. When a mate in 3 feels less like searching and more like recognising, try mate in 5. Two more moves sounds small, but the number of lines you have to check grows quickly, so expect to slow down again. The same goes for 7 later. Dropping back a level for a while is part of the process, not a failure.

A puzzle a day

Shogi365 is the app I made for this kind of practice. It has 1,000 puzzles at each of mate in 3, 5, 7 and 9, all generated and checked by its own solver: a unique first move, a unique attacking move at every step, and no idle pieces. The board enforces the rules above, including drop pawn mate and two pawns, so you learn them by playing. A line that ends without mate can be retried up to three times. There is a daily challenge that everyone gets on the same day, a streak, and stats for each length. It works offline, with no account and no ranking. The app is free with ads, and a one-time purchase removes them.

If you are just starting, I would stay with mate in 3 longer than feels necessary. It is where the habit of reading gets built.