Omega Puffstool

The Omega Puffstool is the final boss of Pikmin: The Return of the Puffmin. Olimar refers to the Omega Puffstool as his nightmare because, the day after he first sees it, he has a vivid nightmare about the beast killing and overtaking him and his Pikmin. Upon its defeat, the Omega Puffstool yields the final Puffshroom.