Cloyster

Cloyster, known in Japanese as パルシェン (Parshen), is a dual-type Water/Ice Pokémon introduced in Generation I. It evolves from Shellder when exposed to a Water Stone. Cloyster is characterized by its large, spiky purple shell, which serves as both a defense and an offensive weapon. Its head resembles a black pearl, with a white, horn-like protrusion above it. Cloyster can swim by propelling water from its body and uses the same mechanism to launch spikes at its foes. The shell is incredibly hard, capable of withstanding bomb blasts. Once shut, it's virtually impossible to open from the outside. While it boasts incredible defense, Cloyster is vulnerable to special attacks. It resides on the seabed, where it hunts for Slowpoke tails.