The Gomoku Sacrifice: Giving Up a Stone to Buy the Tempo

Move Nine, and a Three That Is Already Dead

Your three sits on e5, f5 and g5. d5 is empty. h5 has been his since move six.

That shape still makes a four. Play d5 and you hold d5 through g5, with c5 the only cell that turns it into five. He blocks c5. Your four is gone, and so are the four stones you spent building it.

Most players fire that four the moment they see it. Stronger players hold it until the one move it buys is the move that finishes the game.

That is a sacrifice in gomoku: a stone you place knowing it will never be part of your five. Whether to give it up is never the question. What comes back is.

A Sacrifice Is a Purchase, Not a Gift

The board sells one thing. A move where his reply is not a choice.

Everything else is noise. Shape exists to produce that move. Territory does not exist in this game at all. Stone counts are a scoreboard nobody reads. When you place a stone that is going to die, you are buying a tempo, and tempo has a price list.

• A four with one exit buys exactly one forced reply. It costs one stone and the whole line.
• A live three buys one reply as well, but he picks which end. If you needed a specific point kept empty, you did not buy that point.
• An open four buys nothing. It ends the game, which is a different transaction.

That list explains why strong players keep firing fours while weak players keep building threes. A four's reply is fixed. A three's reply is a menu.

Price It in Moves, and Count What He Keeps

The step that gets skipped: a forced block is not free for you. He places a stone, and the stone stays.

Fire the d5 four and he answers c5. Eight moves later you want a fork on the c-file, and the crossing point you need is c5. It is his. The tempo cost you the stone you played and the square you handed over.

So the real price is one move plus one of his stones inside the region you plan to use next. If your finish needs three empty crossing points inside a five-by-five box, two of his free stones can close that box for good. That is the budget you are spending against.

Sacrifice One: The Line That Was Never Going to Live

Every dead three is a four you have not cashed yet. Paying one stone for it is fine. Doing it on the wrong turn is not.

Cash it on the turn your second shape becomes a double threat, not the turn you notice the four. Fire at move twelve and his block lands while your fork is still forming, inside the exact box you were going to use. Fire at move eighteen and the block does not matter, because the next move wins.

One check before the stone goes down. Count the exits on the four you are about to make. Two exits means it is an open four and the game is already over, so stop planning and play it. One exit means the line dies with his block, and the tempo is the whole return.

Sacrifice Two: The Block That Is Also a Four

His three runs e9, f9, g9 with d9 and h9 empty. You have to block. The two ends are not the same move.

Take d9 when your column already holds d6, d7 and d8 and d5 is his. The block makes d6 through d9 a four with one exit at d10, he has to answer it, and the stone you owed him became the tempo you needed. Cost: nothing extra. You were going to play there anyway.

This is the cheapest move in gomoku and it gets missed constantly, because blocking feels like paying a debt. Before you block on reflex, check whether either end extends a line of yours into a four. If neither does, the block is a pure loss, and the question changes to whether one of your fours arrives before his five.

Sacrifice Three: The Three That Hands Black a Foul

In renju, Black loses outright on a double three, a double four, or six in a row. White's cheapest win is a three aimed at a crossing point.

Put your three on row 11 with its block point at g11, and let Black hold two lines that both cross g11. His only natural answer completes two fours at once. He may not play that move, so he cannot block, and your three is an open four on the next turn.

That three is a sacrifice in the literal sense. Aimed at a crossing, it points at no five of yours; the stone will never be part of your row. You paid a stone with no future for a block he is forbidden to make.

Count the crossing lines before you play it. Two fours at his block point, or two live threes, or one of each. A single four is not a foul, and the whole tactic collapses if you count it wrong.

The Condition Nobody Skips

A sacrifice is a payment, so it needs a receiver.

With one shape on the board, the tempo has nowhere to go. You spend it on a quiet move, he spends his free block stone on something that helps him, and the exchange is a straight loss. It fails quietly, which is why players keep repeating it.

Name the move before you fire. Out loud, if that is what it takes. He blocks c5, I play h7, h7 makes a four-three. If you cannot finish the sentence, it is not a sacrifice. It is a donated stone.

The receiving threat has to be real rather than hoped for. A four-three that needs his cooperation is not a receiver. Building forks is where that gets tested; a bought tempo only pays when the second threat survives his best reply.

Where a Chain Stops Paying

Each four in a chain costs you a stone and hands him one. Four fours is a normal budget. Somewhere past the sixth, his forced blocks have filled the region your last four needs, and the chain dies of crowding rather than defense. Ladder chains are where that limit shows up first.

Two rules keep the budget honest. Do not fire a four whose block lands inside the box where your finish lives. And do not spend two tempi building a shape that needs three.

The second rule sounds obvious and is not. Most lost games are not lost to a bad plan. They are lost to a good plan one move short, paid for with a stone that was still alive.

A Drill That Teaches the Price

Play ten games against Medium with one restriction: you may only play a four if you can state the move you will play after his block, before your stone lands.

Keep score. Count how often the named move was still available when your turn came. Early on it lands about half the time. That gap is the price you had been ignoring.

Then go through your losses looking the other way. Find one block you made on reflex where the other end of his three would have been a four for you. There is usually one per game. The advanced material treats forcing sequences as the backbone of attacking play; this page is only about what the forcing costs.

Cash One Dead Line, Late

Open a board and play ten quiet moves. Find a three of yours that can only become a four with one exit.

Leave it alone. Build the second shape first. When the second shape is exactly one move from being a double threat, fire the dead four, take the block, and play the move you named.

It feels slow. It is the difference between knowing a tactic and owning one.