A pure abstraction.
The goal is to be the first player to pose the fourth different forms of a line, a column or a square zone.
Each turn the players will put one of their pieces on the boardgame. It's forbidenn to put a shape in a line, a column or an area on which this same form has already been posed by the opponent.
We can only double a shape if we have played the previous one himself. The first player who places the fourth different form in a row, column or zone wins the game immediately, no matter who owns the other pieces of that winning move.