Bionicle Légendes, tome 7 : Prisoners of the Pit

Far below the surface in the darkness of the great ocean depths where no Toa has ever gone before, there lies a strange and mysterious habitat known as "the pit." It's a place of unknown dangers and bizarre creatures, ruled by six merciless deep-sea monsters whose likes the surface world has never seen. They dominate a world where the rule is eat or be eaten. Welcome to a world of darkness... Welcome to the realm of the Barraki.