Gomoku is a simple game with deep tactics: two players take turns placing black and white stones on a 15×15 board, and the first to make an unbroken row of five wins. Here’s how to play and how to start beating the computer.
The basics
Stones go on the points where the grid lines cross, not inside the squares. Black always moves first, then each player places one stone per turn. Stones never move and are never captured.
The first player to line up five of their stones in a row (across, down or diagonally) wins. If the board fills up with no row of five, the game is a draw.
Five or more, or exactly five
Five or more (freestyle) is the usual rule: a row of six or more also wins.
Exactly five: a row of six or more doesn’t count, for either player, so you have to finish with exactly five.
You can pick the rule, your color (black, white or take turns) and the difficulty when you start a new game.
Placing stones
Tap or click a point to place your stone. The red dot shows the last stone played.
On a phone, the first tap shows a see-through stone with guide lines so you can check the point. Tap it again or press Place to put it down, or slide your finger to move it.
On a keyboard, use the arrow keys to move the ring and Enter or Space to place.
Undo takes back your last move and the computer’s reply. Resign ends the game as a loss.
Threats you must know
A four is four in a row with one open end: it threatens to win next move, so it must be blocked.
An open four has both ends open and can’t be stopped. That’s why an open three (three in a row with room on both sides) must be blocked right away.
A four-three (one stone making a four and an open three at once) almost always wins: your opponent can only block one.
Watch the diagonals. They’re the easiest lines to miss.
Beating the computer
Easy misses some of your threats, so it’s a good place to practice building open threes. Normal blocks well and sets traps of its own. Hard reads long chains of forcing moves and punishes any open three you leave alone.
Black has the advantage of moving first. Once you can beat a level as black, try it as white, where you’ll need to defend carefully and wait for your chance to counterattack.