Eliminate all tokens except one.
To move a token, click a nonempty from-position, then a nonempty target position (you may click the from-position again to unselect it). A selected token will temporarily change its color.
A token can move up, down, left, or right as far as the number on the token indicates.
Such a move eliminates the token at the target position, and the number on the moved token increases by one.
You win when only one token is left on the board.