Poliwag is an amphibian Pokémon resembling a blue, spherical tadpole. It has large eyes and pink lips that can also act as suction cups for rocks. Its skin is very thin, but flexible and difficult to puncture. There is a black and white swirl on its abdomen, which is actually its internal organs showing through its semitransparent skin. The swirl is clearer following a meal and will have a white tinge if the Pokémon is affected by disease. The direction of the belly spiral differs by area; the equator is thought to have an effect on it. (Source: Bulbagarden.net, CC BY-NC-SA)