The Mate is a traditional South-American infusion drink, very popular in Argentina, Paraguay, Brasil and Uruguay. It's traditionally drank socially with friends, family or co-workers. The same mate is used by everyone and one person, the “cebador”, takes the role of server.
Simon Wants Mate is a memory game (kinda like Simon) where we try to poke fun at the “stress” the cebador is put through when he/she makes mate for a rough crowd. In each round of mate the drinkers may want a “bitter mate”, “sweet mate” (with sugar), a "medialuna" or simply to pass a round. You have to remember what each drinker had the last but also pay attention to any change in their needs (though the situation would most likely not go like this in the real world).