Black plays first, then turns alternate. On his turn, a player must perform exactly one of the following actions:

a) Place one or two stones of his color on empty points of the board. On his first turn, Black can only place one stone. In any case, at the end of a turn, any two like-colored, diagonally adjacent stones must share at least one orthogonally adjacent, like-colored neighbor.

b) Flip one enemy stone which is sandwiched between two friendly stones adjacent to it on the same orthogonal line. This kind of move is illegal if said enemy piece isn't orthogonally adjacent to any empty point.

The game is won by the player who completes a chain of orthogonally adjacent stones of his color touching the two opposite board edges of his color. Draws are not possible.