|Spoiler Alert: This wikia contains details about future plotlines described in the light novels. Do not proceed unless you want to be spoiled. |
|Affiliation||Water Elemental Lord|
Leviathan or Sea King Leviathan is a strategic-class possession-type militarized spirit. It was also a trusted commander serving the Water Elemental Lord.
According to war records, Leviathan destroyed a city in merely seventeen hours of operation.