Leviathan is a hybrid creature, having features of a whale and an eel. It uses its three eel-like tails to swim through the air as if it were water. Though its mouth resembles that of a baleen whale, it has sharp teeth, a feature exclusive to toothed whales. To give one a sense of perspective, Dante can fit inside of its eye. Its heart and lungs can be considered their own entity, and one that will protect itself with dark energy spheres and red lasers. Leviathan's digestive tract is populated by two Gigapedes and many Hell Envies.
Leviathan is a biological weapon created by Mundus. Its body is a gateway to the Hell of Envy, and the souls of those sent to Hell for jealousy are its power source. Sparda sealed it away along with Temen-ni-gru, but it was released by Vergil and Arkham.
Leviathan swallows Dante as he is running down the tower after awakening his Devil Trigger, and Dante wanders throughout its entire body until he slays the beast's heart, causing it to die and fall onto the Subterranean Garden. Dante then escapes out of its eye.
- Leviathan's name and design are based off the Leviathan creature of legend.
- Leviathan's role as a gateway to the Hell of Envy is a reference to the concept of Hellmouth.
- The Leviathan shares his origin with Nightmare, a boss from the first Devil May Cry game, as they both are biological weapons created by Mundus.
- In fact, the design on Leviathan's heart and its behavior, down to the sound file used for its pained scream when its lungs are injured, are the same as those on the Nightmare.
- Leviathan, along with the other gatekeepers of the Temen-ni-gru, represent one of the Seven Deadly Sins. Leviathan represents the Sin of Envy.