The Pelagic Megathrust Leviathan, also known as the Great Erasers, resides in oceanic trenches and is characterized by its colossal, blind, serpentine body that can reach lengths of up to 400 feet and weigh between 50,000 to 60,000 tons. It is believed to be ancient, with sightings linked to catastrophic tsunamis. This species possesses a unique ability called Gravitational Displacement Pulse, which generates shockwaves that can lead to massive tsunamis. They filter feed on the energy from tectonic activities and are effectively immortal, growing until they die from sheer mass or cataclysmic events.

Socially solitary, these creatures communicate through deep infrasonic rumbles and reproduce only once every ten millennia. While they are considered indifferent to the destruction they cause, they are integral to coastal ecosystems, revitalizing them through their tumultuous movements. Despite their destructive nature, they are revered and feared by humankind, often viewed as gods of destruction, with cultural phrases like "waking the leviathan" reflecting the catastrophic consequences of their actions. The existence of this species is largely inferred from barnacle-encrusted remains found after significant tidal events.