"What do you mean, I have to figure out the rules myself? How can I play this game if I don't know the rules?" Mao. The only game in which the rules of the game prohibit me from explaining the rules to you...
Mao is a standard deck playing card game where the object is to get rid of all your cards, and this is the only thing that new players are told about this game. They are forced to figure out the rest of the rules by themselves. Every time a player breaks a rule, a penalty is called, and they must take it back and draw a penalty card.
In some variants, the winner of each round makes up a new (secret) rule for the next round.