Corphish is known as the Ruffian Pokémon, and can be found on Route 7 by fishing from the stream there. It is a water type that evolves into Crawdaunt at level 30.
It is described in Pokemon Emerald:
- Once it grips prey with its large pincers, it will never let go, no matter what. It is a hardy Pokémon that can thrive in any environment.