Their uniqueness is fascinating to say the least. Especially seeing how they evolved in reaction to the depths, when there is very little light from the surface, all the fish have gigantic eyes, and predators use light to attract their bait, tons of creatures that can generate light by themselves there. One fish could make himself "invisible" in a way that he looked just like the water surface if looked at from below.
Then as you go deeper and there is absolutely no light at all, a lot of the creatures (some are pretty big like the abyssal grenardier) have no eyes anymore, tons of carrion eaters that feed on the corpses of animals that fall to the bottom of the ocean. When you get like, Mariana Trench bottom depth, there's hydrothermal vents down there called black smokers that puke out sulfide, and all the creatures down there actually feed off that, crazy.
Too many shitposters so far, but bump for potential.
Huh, that must be what the sandshark from Korra is based off