Rockgrub in Subnautica: Below Zero

RockgrubScavengers and parasites in the game's databank. Rolled for each new game at 149 to 675 m deep.

Data: Subnautica: Below Zero game files (build of 12 Aug 2025), read and drawn by PinDrop. (c) Unknown Worlds Entertainment. PinDrop is fan-made and not affiliated with Unknown Worlds Entertainment.

Map of Subnautica: Below Zero with the Rockgrub drawn on it
heat = where it can spawn (model)Open the map →
Class
Scavengers and parasites
Depth
149 m to 675 m
Spawns per game
about 337
Placed pins
none

“A small, luminescent scavenger, roughly thumb-sized. This creature may be a distant relative of the sand shark, sharing that species' unusual limbs, segmented exoskeleton and burrowing behavior.”

Assessment: Harmless

Rockgrub, in-game databank. The studio's text, quoted short.

Where Rockgrub spawns

Median depth 523 m; 10% of the modelled spawns lie deeper than 675 m and 10% shallower than 149 m; the baked slots that can hold it span 824 m to 1 m.

Areas where Rockgrub can spawn
AreaSlots that can hold itExpected per gameShare
Crystal Caverns4,714196
Koppa Mining Site4,527126
East Iceberg Zone2,23611
West Iceberg Zone1,0164.1

Spawn numbers are a model read from the game's spawner tables and 921,892 baked slots, not verified in a running game.

In the same places

The area Rockgrub appears in most is Crystal Caverns. What else spawns there:

About the Rockgrub

The Rockgrub is filed under scavengers and parasites in the game's databank. The files give it 12,493 baked slots that can hold it across 4 area groups, 337 expected spawns per new game, mostly in Crystal Caverns, at 149 to 675 m deep for the middle 80%.

The files do not say how it behaves or what it can do to the player, so this page carries only the studio's databank text above. Depths are metres below sea level; coordinates are the game's world metres, x east and z north.

Spawn numbers are a model (slot tables), not verified in a running game. Placed pins are read as placed.