Metapod

thingiverse

Metapod is the Pupal Pokémon. It's found in the wild early on in the Kanto and Johto regions, where its larval form is Caterpie, a caterpillar-like Pokémon. Metapod evolves into Butterfree, which resembles a butterfly. Despite being classified as a cocoon Pokémon, it closely resembles a chrysalis instead. Its exterior hardens regularly to protect its soft innards while undergoing metamorphosis into Butterfree. Metapod barely moves in order to conserve energy for this process. The shell that protects it is said to be as hard as steel, but a sudden impact could still cause it to burst open and expose its vulnerable body completely.