Known as the "worm" Pokémon, was based on the design of the caterpillar of the Swallowtail butterfly. Caterpie has green skin with a yellow underbelly, yellow spots, and large red osmeterium protruding from its forehead. Their green bodies are useful for camouflage in foliage, their eyes are patterned to scare away predators, their suction-cup feet allow them to climb any surface, and the osmeterium on their heads can project a horrid stench to repel predators. Caterpie is the smallest of all the original Pokémon, and grows in size by shedding its skin. Eventually, Caterpie evolves into Metapod, and then Butterfree.