Gastrodon is a sea slug-like Pokémon. Much like its pre-evolved form, it has a slug-like body with a round head and a mantle covering the top half of its body. It has six stubby legs and three black eyes with white pupils. A yellow stripe runs along the edge of its mantle, through its lower two eyes, and around the back of its head. Like Shellos, Gastrodon has two forms based on the sea it lives in. In its West Sea form, it has a pair of large tentacles on its head that curve upward, as well as a smaller, straighter pair of tentacles on its neck. Its underside is pink, while its mantle is brown with three pink spots on each side. There are two lumps on its back, resembling the cerata on real-life sea slugs. (Source: Bulbagarden.net, CC BY-NC-SA)