Gomoku

Gomoku, also called Five in a Row, is a traditional board game with one rule: the first player to line up five stones wins. You play dark and the computer plays light, taking turns to place a stone on any empty crossing point. Lines may run across, down or along either diagonal.

The rule is simple but the play is sharp. A row of three with both ends open has to be answered straight away, and a row of four with both ends open cannot be stopped at all. The winning idea is usually a double threat — one stone that creates two lines at once, so your opponent can only block one.

Place stones in turn. Make an unbroken line of five in any direction before the computer does.