The Leviathan is a type of huge sea-monster known to inhabit the Endless Sea.
One specimen of Leviathan was captured by Samukai in order to keep Dr. Julien in his prison. In The Last Voyage, he caught the Destiny's Bounty in his tentacles and was going to crush it until Zane jumped overboard and used Starteeth to free the creature.
This Leviathan, or another, later came under the influence of dark matter from the Dark Island and attacked the Ninja.
- Ninjago: Masters of Spinjitzu
- The Dark Island Trilogy
- The name Leviathan refers to a sea monster spoken of in the bible, in this case, similar to the Kraken, a squid like beast.