The game consists of a set of 81 tiles. Each is identified by a unique combination of four features: Form of the symbol, Colour of the symbol, Size of the symbol, Background colour. Each player starts with 10 of these tiles; goal is to get rid off them.
On his turn, the player may either swap one of his tiles; or he places a series of tiles on the table, where a pattern is formed the these tiles. Afterward, he always draws one tile; either from a small face-up supply, or from the bag.
A tile may only be placed adjacent to another one where 3 out of the 4 features are identical. In his turn, a player may place several tiles, but each tile after the first one has to be adjacent to the last tile he just played. There's a special award for placing a tile adjacent to at least two other tiles (within the placement rules).
The first player who has places his last tile wins the game.