This article is about the Rockgrub in Below Zero. To see this subject's article on the Subnautica Wiki, click here.

The Rockgrub is a passive fauna species. Despite superficially resembling an invertebrate, the PDA states that it is a possible relative of the Sand Shark.


The Rockgrub is tiny in size. Its body is slim, round and segmented. It also has two swimming fins on either side, and a larger flipper serving as the tail. The creature has five appendages on each side of its body, and a circular maw containing many small teeth.

The Rockgrub's most notable feature is the constant, bright bioluminescent green glow that its entire body emits to light up a small spherical area around itself.


The Rockgrub swims rather quickly within its vicinity, seemingly scavenging whatever it could find. They are most visible in darker areas such as caves.