Submarine Fish is a water creature that can be found in the pool of The Sewers Room which has the Nopperabou Ghost within. Most of the time entering the room will show there has a moving shadow in the pool, some times it will show a Sewers Pirori swimming, and 1/8 chance will show the Submarine FIsh that has an eye with its long body floating on the water.
It can only react with Cat effect. Like other water creatures it can't be reached.
- In the game's files, there is an unused version of the Submarine Fish that appears to be half-finished.