Pirogusu

The Pirogusu is an enemy found in The Legend of Zelda: A Link to the Past. The only dungeon it appears in is the second dungeon in the Dark World, the Swamp Palace. It is a small fish-like creature that appears in pipe holes on the walls, dropping down to the shallow water below to attack Link. It will swim around infinitely unless it is defeated by one of Link's many items. The pipe also continues repetitively spewing Pirogusu out every so often until Link exits the room.