Row of five
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This is the winning line. A row of six also wins in this freestyle version.
Gomoku guide
Board, patterns, and practical Gomoku tactics
Gomoku is simple to start—make five stones in a row—but the decisive moves are usually threats that force a reply.
Board and rules
Gomoku is played on intersections of a 15 by 15 grid. Black starts and players alternate placing one stone on an empty intersection. A continuous horizontal, vertical, or diagonal line of five or more wins this site’s freestyle game. The centre and four nearby dots are reference points, not mandatory moves.
Rule sets differ. Our game does not use Renju’s Black restrictions, exact-five-only wins, captures, passes, or swap openings. That matters because a double-three is a strong tactic here, while it can be illegal for Black in Renju.
Read the threat shapes
Four in a row
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A one-ended or broken four has one immediate winning square. The opponent must block that square unless they can win first.
Open four
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Both ends complete five. With no simultaneous winning move of their own, the defender can block only one end, so an open four is a forced win next turn.
Open three
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An open three can become an open four. A closed or false three has a blocked end or cannot create two winning ends.
Forks: two threats at once
A fork makes the opponent answer more than one threat. A four-and-three creates a winning square and a developing open three; a double-four creates two distinct winning squares; a double-three creates two open-threes that can each become an open four. If the defender cannot cover every immediate winning square, the attack is forced.
Do not assume every pair of nearby lines is a real fork. Check that each line has enough empty space and that the defensive move cannot block both threats at once. In Renju, Black must also consider forbidden-pattern rules; in this game those restrictions do not apply.
Early-game strategy
Start near the centre because it gives your stones room in every direction and makes it harder for the opponent to isolate your first line. Build connected shapes with two or three directions available instead of extending one obvious row too early. When the computer creates a four, block it immediately; when it has an open three, look for a move that blocks the future four while improving your own shape.
There is no universal, guaranteed opening win for an unrestricted human game from a short fixed recipe—the strength of a position depends on precise replies. Treat “forced win” as a claim to verify move by move: it is reliable only when each defense leaves an immediate, separate winning threat.