Bottomless??

The abyss is full of monsters and odd fish. Some theoretical (giant stingray) and some just strange (angler fish). The main reason for not knowing all about this part of the ocean is mainly because the water pressure is so intense that most living things will die. Another reason is most  submarines do not have enough oxygen to get to the bottom.

 

As far as we know the animals may be this big.

Or this weird.

In the end the abyss is full of monsters known and unknown. And we may never reach the bottom.

But the abyss will never seem to stop being amazing.