Serperior is a primarily pale-green, snake-like Pokémon. Serperior has curled pale-green patterns on the sides of its face and snout, and small, pointed yellow extensions on the back of their heads. Its face and upper neck are white-colored, and curled, tendril-like darker green extensions spread out from the sides of its lower neck, forming a curling pattern lower down the body, resembling a fancy collar. It has narrow red eyes, and small, pointed teeth on its lower jaw. The upper section of its body is dark green, and the lower pale green. Curled yellow patterns adorn its body, and a sprig-like feature of several leaves tip its tail. It has lost its legs completely, and now only has small, stubby hands.