About the game
Gomoku, also known as Five in a Row, is a traditional board game in which black and white take turns placing stones, and the first player to line up five in a row — horizontally, vertically or diagonally — wins. The rules fit in one sentence, but every stone flips the balance between attack and defense, making it a deep battle of reading and anticipation.
This version uses a standard 15x15 board and supports two modes. In vs AI you take the black stones against the computer; in 2 Players mode two people alternate turns on one device. The AI is a heuristic opponent that builds and blocks open threes and fours — drop your guard and it will construct an unstoppable threat before you notice. Your win count is tracked, so see how long a streak you can build against it.
How to play
- Tap (click) an intersection to place the current player's stone.
- Switch between vs AI and 2 Players with the mode buttons (switching starts a new game).
- Press Restart at any time to begin a fresh game.
Rules
- Black moves first, then black and white alternate one stone per turn.
- The first to connect five of their stones in any straight line wins.
- Stones cannot be moved or taken back once placed.
- If the board fills with no winner, the game is a draw.
- This is freestyle Gomoku: no renju restrictions such as the 3-3 ban.
Strategy & tips
An open three seizes the initiative
A row of three with both ends free is a threat your opponent must answer immediately. When extending your stones, always prefer shapes whose ends are not blocked.
Block fours always, open threes instantly
Four enemy stones in a row means defeat next turn, so blocking outranks any attacking idea. An unattended open three becomes an open four that cannot be stopped — cut it off one beat early.
Hunt for double threats (3-3 and 4-3)
The classic winning formula is a single move that creates two threats at once. Your opponent can only block one, and the other wins the game. Watch the intersections where your lines cross, especially where diagonals overlap.
Start near the center
The center offers the most room to build five in every direction. Spend your opening moves establishing presence within the central 5x5 area, then choose your direction based on how your opponent's stones flow.
FAQ
The AI is too strong (or too weak). Can I change difficulty?
The AI has a single difficulty level. It is good at completing fours and blocking open threes, but it does not read deeply — practice building double threats and you will beat it consistently.
Are renju rules like the 3-3 ban applied?
No. This is freestyle Gomoku with no forbidden moves. Both black and white may freely create 3-3 or 4-4 formations.
Does a line of six or more count as a win?
Yes. Any line of five or more stones wins (overlines are allowed).
How are my results recorded?
Wins in the current session are shown as your score, and your highest win total is kept as the best record in your browser's local storage.
