The Poison Mushroom is an item that debuted in Super Koopa Kart. After that game, it goes into a 16 year absence until Koopa Kart Wii. this item appears in all Koopa Kart games since Wii. It acts like a Banana in that it can be placed behind the player and block items. It does the opposite of what the Mushroom does: it slows down the player upon contact, while the Mushroom speeds him or her up. The Poison Mushroom looks like a Mushroom, but it has a purple cap. It had green spots on its purple cap in Super Koopa Kart, but as of Koopa Kart Wii, it has pink spots instead, similar to what would become its Super Mario 3D Land design.