Leviathan Class Organisms

Leviathan is a classification given to extremely large creatures. Although the wording of the Reaper Leviathan's data bank entry would seem to imply that the leviathan classification is exclusive to predatory life forms, this is not the case; any fauna species of a suitable size can be classified as a Leviathan.

Leviathan is not part of a taxonomic classification so does not imply any of the species classified as such are related. In fact, the only two that appear to have any close relation are the Sea Emperor Leviathan and Sea Dragon Leviathan who share several features including an almost identical body shape, seven identically positioned tentacles, forelimbs and light producing organs protruding from their snouts.

Despite being enormous when compared to the fauna of Earth, the leviathans inhabiting Planet 4546B in the present day are dwarfed by their predecessors; the three million year old Gargantuan Fossil at completion measured an estimated 6-8 times longer than a fully grown Sea Emperor specimen. To support a predator of such titanic proportions, many of the other creatures of that time period must have also been similarly sized or larger.

Although the term "Leviathan" is used to refer to an aquatic creature in the real world, there is no confirmation on whether or not the Leviathan classification is restricted to aquatic fauna in the Subnautica universe, or is simply the term used for any species of a sufficient size.