Catfight is a very fast two-player card game in which players compete to have the strongest gang by trying to collect as many different cats as possible. Each turn, they draw two cards then either discard one card or lay down a set of cards. To lay down a set, you need at least two cards if the same gang member hasn't been played or more cards than are already on the table if it has been played. Any cards of the same gang member on the table are discarded. The round ends when one player has five different gang members, OR the draw pile is exhausted. When the draw pile is exhausted, players score for the different gang members they have laid down in front of them.
Just like in a fighting game, Catfight is played as "first-to-2", or I think it's also known as best of three.
—description from the designer