You need 5 or more players. A certain number of keys are placed in the center of the square. 4 cards are distributed to each player. Players quickly exchange cards, and their goal is to get two similar cards. When two similar cards are obtained, they can be placed on the floor and the key can be received. The player who does not obtain a key in the round is eliminated. The rounds continue until one of the players wins by collecting the key in the last round.