The Crazy Castle is a large, inflatable castle and one of Witchyworld's attractions, being located in the Wild West-themed area. In Banjo-Tooie, the castle is deflated on arrival but can be inflated by activating the "Pump Master 2" in the pump room.
Once the Crazy Castle in accessible, two mini-games can be played inside: the Hoop Hurry Challenge and the Balloon Burst Challenge.