Every spring, millions of monarch butterflies leave Mexico to spread out across eastern North America. Every fall, millions fly back to Mexico. However, no single butterfly ever makes the round trip. Mariposas is a game of movement and set collection that lets players be part of this amazing journey. Mariposas is played in three seasons. In general, your butterflies try to head north in spring, spread out in summer, and return south in fall. The end of each season brings a scoring round, and at the end of fall, the player with the most successful family of butterflies — i.e., the most victory points — wins the game. —description from the publisher