Leviathan serves as a soldier in the global terrorist group Humarise, dedicated to the eradication of Quirk users. His Quirk unleashes violent aquatic currents, capable of twisting and surging with devastating force in battle. Under Flect Turn’s command, he aids Humarise’s campaign of global chaos by deploying Trigger Bombs—devices that release a destabilizing gas, forcing Quirks into catastrophic spirals and annihilating those who wield them. Leviathan’s imposing physique mirrors the destructive might of his water-manipulation abilities, embodying Humarise’s fanatical crusade against superhuman powers. No records detail his origins, motivations, or personal history within official documentation. His documented role remains strictly operational, focused on frontline engagements without elaboration in supplementary materials such as spin-offs or films. Canonical sources provide no insight into his activities after the events of *World Heroes’ Mission* or his ultimate fate post-Humarise’s downfall.