In Crash Bandicoot Purple, trading cards can either be found hidden in the game's worlds, bought/earned in Moneybags's shop, or earned by completing Crunch's weightlift mini-games. Each card has a different object, place, or character, and they serve no specific purpose beyond counting towards your completion percentage.
Trading cards can also be acquired by linking Crash Bandicoot Purple to Spyro Orange, requiring two players to work out a trade. The Polar card can only be acquired by linking two copies of Purple together.
Limited editions of the game were shipped with real life trading cards containing descriptions for some of the characters: Crash, Coco, Crunch, Cortex, and N. Trance.