"This creature is approaching the size limit for sustainable organic lifeforms, and has been designated leviathan class. Adults of the species have been encountered exclusively around the edges of the volcanic crater which supports life on this part of the planet, and react with extreme aggression on approach.

Hammerhead:
Cartilaginous extensions of the creature's skull form a hammerhead which protects the ghost leviathan as it performs devastating ramming attacks.
Jaws:
While fully capable of tearing through the flesh of any creature in range, all evidence indicates that mature ghost leviathans feed on microscopic lifeforms in the waters around the edges of the inhabited zone. Their vicious attacks on interlopers to their domain are not predatory in nature, but territorial. A creature so vast requires a huge expanse of water to satisfy its daily calorie requirements.
Torso:
Its muscled interior body is surrounded by a translucent outer membrane, suggesting adaptation for deep, low-light environments. When threatened it can tense its entire body before lashing out with incredible speed.
Lifecycle:
Probable migratory behavior. This specimen was likely born far from the area where it was encountered.
Assessment: Extreme threat - Avoid the crater edge"