Chompasaurus is a large plesiosaur found in the lake inside the mountain in Terrydactyland. Banjo and Kazooie meet him when they jump to the top of the tall island in the middle of the water using Springy Step Shoes. He comes out of the water and swallows them (Banjo and Kazooie must learn bird handling). He then tells Banjo and Kazooie that he needs their help to kill his stomach ulcers. Once the problem is solved, Banjo and Kazooie are rewarded with a Jiggy.