The Reefback is a passive, leviathan class fauna species. It is the second largest passive life form, and the fourth largest life form in the game, behind the Sea Emperor Leviathan, Sea Dragon Leviathan and Ghost Leviathan.


The Reefback is massive in size, with most of the creature's body being comprised of a thick, dark-blue carapace having a rounded, triangular front, and a relatively small body concentrated in the posterior. Attached to its main body are three long whip-like tentacles.

An adult Reefback has patches of teal-colored coral and brown-colored grass growing across its carapace, befitting its name. The carapace has a slightly bright blue dotted pattern across towards the back. Beneath its carapace, it is dark green with light blue bioluminescent stripes on the sides and in the middle. On either side of its body are eight yellow bioluminescent bulbs. The purpose of these is unknown, though the data bank entry notes a visual similarity to the Gasopod algae gland. They could also be very underdeveloped eyes, which might suggest the Reefback has some other means of "seeing" its surroundings. Two siphon-esque structures that constantly expand and retract as the creature moves are located next to these bulbs.


The Reefback drifts slowly and gently around the open waters of many biomes, mostly seen swimming in pods of more than two. It almost never adjusts its current altitude, unless bumped against obstacles.

Juvenile Reefbacks are a quarter the size of an adult. They can often be found with adults in certain locations.

The Reefback will frequently emit a range of echoing, low-frequency calls. They will only emit these calls if there are other Reefbacks nearby; if not, they will be silent. This suggests that these calls are a form of communication, as opposed to echolocation.

When Reefbacks are exposed to damage, their tentacles will wave quickly and they will move slightly faster for a brief period.


Adult Reefbacks can support mini-ecosystems on their back. These ecosystems include many types of flora and coral, along with other small fauna swimming in the vicinity of the gentle giants. Some caution should still be taken when approaching Reefbacks, as Tiger Plants often make their homes on their backs.

Energy Value

ReefbackArrow-right (1)BioreactorArrow-right (1)Energy×5000
Reefback EggArrow-right (1)BioreactorArrow-right (1)Energy×250

Data Bank Entry


Limited data available. The microcosm of life on the creatures' shell plates indicates advanced ages between 100 and 300 years old.

  1. Chitinous Plating:
    The creature's armor plating is thick enough to interfere with the spectroscopic analysis.
  2. Unknown Pods:
    Unknown purpose. Green in color. Visual similarity to glands seen on other creatures.
  3. Tentacles:
    Total length ranges upwards of 25m. Provide low speed propulsion.

Sociable, seen travelling in small pods, behavior consistent with low-level sentience.

Predators: Unknown

Assessment: Additional research required


For a more complete gallery, see Reefback/Gallery


  • Reefbacks were initially intended to submerge themselves in sandy areas. Increased activity about them would have made them rise in search for a peaceful place to rest.[1] It is unknown if this will be implemented.
  • Another intended interaction would've been that the player could grab a hold of a Reefback's tentacles to hitch a ride or hide on their plant-covered backs to hide from predators.[2] It is unknown if this will be implemented.
  • Reefbacks used to be much smaller than they currently are, and had the same texture that is currently given to juvenile Reefbacks