This section temporarily contains information copied directly from Bulbapedia, and needs to be rewritten so not to be classified as plagiarism.
Mudkip is a small amphibious quadruped Pokémon. It has a blue body with a light-blue underside. It has a large head with a blue fin on top, and a light-blue tail fin. It has black, beady eyes and orange, star-shaped gills on its cheeks. By using the fin on its head, Mudkip is able to detect changes in air and water currents as well as bodies of water. Its fin can also point in a certain direction, as seen in the anime. Mudkip is capable of moving or crushing boulders larger than itself. Its large tail fin propels it through water with powerful acceleration. Mudkip lives in swamps and other wetlands, where it sleeps by burying itself in soil at the water’s edge.