The conditions in this cave support a microcosm of unique, possibly predatory lifeforms. Try to anticipate unanticipated threats.


― PDA, Dialogue


The Jellyshroom Cave is a cave system found below the Grassy Plateaus, Kelp Forest, and Safe Shallows.

An entrance can be found at coordinates 140, -86, -397, and another can be found at coordinates -724, -90, -9.

Both entrances are an approximately equal distance away from Lifepod 5 (Safe Shallows). Both are also inaccessible via the Cyclops due to size restrictions, and although the area is explorable via the Seamoth, it is impractical and dangerous to do so without at least the first Seamoth Depth Module (Mk1 or higher). The Seamoth's perimeter defense system is also advisable (but not required) due to the Crabsnakes’ tendency to ambush the player from the Jellyshrooms themselves. The caves can be explored with the Prawn Suit, but it will be difficult to come back up from the caves, even with the Prawn Suit Jump Jet Upgrade. The best way to exit the cave using the prawn suit is to utilize the Prawn Suit Grappling Arm.


The Jellyshroom Cave is a large cavern characterized by a dense population of huge, translucent, purple Jellyshrooms, along with structures such as stalactites and stalagmites.

The cave system has two predatorial species and two prey species. The most notable of these are the Crabsnakes residing in Jellyshrooms, and the Oculus, both of which are found only in this biome.

Spoiler alert: The following section contains story related material.

The second abandoned seabase built by the survivors of the Degasi can also be found in the Jelly Shroom Caves. The first entrance at 150, -86, -397 is right above the Degasi Seabases but is inside the radiation zone, so you will need to have either fixed the radiation leak or have the Radiation Suit in order to visit the base.

Data Bank Entry

Environment Log

User 'Paul Torgal' requested cross-referencing of local environment scans with ideal habitat construction conditions. Displaying results.

- Large subterranean cavern with multiple entrances
- Conditions support a unique microcosm of predatory lifeforms
- Minor structural instability in cave walls
- Extensive resource deposits

Average Environment Safety Rating: C
Optimal Habitat Site Safety Rating: B

Site 7 has been selected as the optimal habitat construction site for the following reasons:

- Close proximity to one of the cave entrances, in case of emergency
- Medium distance from predatory organisms
- Stable foundations on which to build
- Ready access to materials

A signal tracking the site has been created.



  • The abundance of Stalactites suggests that these caverns were dry-standing for several million years, only later being flooded presumably when the ceiling collapsed due to erosion - this might explain why its native ecosystem is so uniquely different from all bordering biomes.
  • The ambience noise is the same as the Blood Kelp Zones.
  • The Jellyshroom Cave is currently the only biome to feature Large Magnetite Deposits in the game.
  • The PDA will alert the player when they are near an entrance by saying: "local scans show a nearby cave enterance,depth [depth of enterance ], leading to a unknown environmental biome."