The game set includes a deck of 54 illustrated animal cards (two of each of 26 unique cards) and a simplified, yet accurate, evolutionary tree board used for reference during play. Intended for use in homes, classrooms, museums, and other science programs. Based loosely on Go Fish, the goal is for players to collect as many sets of closely related animals as possible. The sets are "clades" of closely-related animals on the evolutionary tree board, which players use for reference. Players take turns asking another player for cards, and if they do not have a matching card, they say "Go Extinct!". The gameplay is more strategic than Go Fish because players can ask either for a specific card or a matching card at any level of the tree hierarchy, thus trading off the specificity of the result for the likelihood of a match. The game is designed to be fast-paced and fun, while familiarizing players with different animal species, common classifying traits, and the 'nested sets' nature of the evolutionary tree.