Within the great Tear, gargantuan beasts roam the clouded void between hemispheres. Their bellowing calls echo throughout the expanse, warning airshipmen and Qoatl settlers alike of their presence, but doing little else to reveal their precise location within the mists until it's far too late. Though they appear to be immune to the noxious Miasma within the Tear, they nevertheless carry it with them, often spewing it skyward when they breach above the clouds to take in fresher air.
Most of the time, Chasm Leviathans are peaceful creatures, fearsome as they may seem. Their miasmatic wake makes them rather dangerous to approach, but they are rarely known to attack even those who intrude upon their space. The trouble - and the source of many a terrifying legend among airship crews - are those few who make it 'rarely' rather than 'never'. When Leviathans see fit to attack, there's very little that can be done aside from flee towards the borders of the Tear as quickly as possible. For those who don't make it, the silhouette of the great beasts against the sky will be the last thing they ever see.
Chasm Leviathans look something like a cross between a whale and a sea serpent, though their bodies are swollen with bulbous gas bags that allow them to stay aloft within the clouds of the Tear. They have four sets of pectoral fins, each progressively smaller than the last as they get farther from the head. Their mouths are gaping, and filled with an arrangement of baleen plates that appear similar to large, jagged teeth from a distance, but are designed to interlock in such a way that larger food can be scissored apart and then filtered of any remaining Miasma once it's down to a manageable size.
Much of a leviathan's body is covered in a thick, bony plating, articulated to allow them to move smoothly and gracefully through the air. These plates are frequently covered in small ecosystems of barnacles and coral that have managed to latch onto them and adapt to the deadly environment of the Tear after falling out of the seas. Despite being naturally white or gray, the leviathans eventually take on a yellowish color reminiscent of spoiled milk or an overripe egg yolk.