Labyrinth Monster

Labyrinth Monster is a character in Hero of Many. Hero encounters him in Labyrinth. Monster died when Hero repeatedly forced it to crash into spines.

Fight with Hero
The fight occurs in the arena. Hero can hide himself behind walls but when he enters the inner arena, monster attacks him. When it happens, Hero has to get back behind walls. The Monster crashes into spines and is injured. As Hero repeats this several times, Monster dies.

Trivia

 * Labyrinth Monster isn't an only Giant Fish in game. The other one is met in level 5 and 6 where it eats Hero and Friend. It is unlikely that its the same creature.