Hexagonal Go-Moku.

The object is to get five of your stones in a row in any direction, straight or diagonally. The diagonals have been color coded on the hex grid so that they are easier to see. Six or more stones (an 'overline') does not count for a win.

Black goes first. On its first move, Black is forbidden from placing a stone on the central hex, marked with a delta. After that, players alternate placing stones on any open space.