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Primary Containment Facility

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This article contains information that is updated for the latest Experimental Version of Subnautica. Players using stable mode may find this information inaccurate.

This article is about the Primary Containment Facility. You may be looking for the Disease Research Facility.

References to the emperor containment facility in the data are scarce, but its location is suggested to be somewhere with volcanic activity, at a depth of approximately 1200m.



The Primary Containment Facility (PCF), also known as the Emperor Containment Facility or Sea Emperor Prison or merely the Prison, is an in-development Precursor Base located within the Active Lava Zone that will serve as the final major story location. It was built by the Precursors around one thousand years ago and is where the last Sea Emperor Leviathan is contained, along with the five remaining Sea Emperor Leviathan Eggs. There are two entrances to the cavern containing the Facility; located at -300 -1270 -150 and 90 -1240 360, southeast and directly north of the Lava Castle, respectively.

The Primary Containment Facility will require the Blue Alien Artifact to unlock, which is found inside the Precursor Thermal Power Generator.

The Primary Containment Facility, like the other Precursor Bases, was built a little under one thousand years ago. It was purpose-built to contain the Sea Emperor Leviathan after it was discovered that it was immune to Carar. The aquarium section was originally all inorganic with several teleporter hubs set up (though none large enough to allow the Sea Emperor Leviathan's escape). However, as creatures began migrating into it, they brought with them flora seeds along with loose sand and mud. Over time, the aquarium became a thriving ecosystem with the Sea Emperor Leviathan at the heart. At an unknown date, the Sea Emperor Leviathan laid five eggs, which the Precursors took and placed in the Incubator Device to stimulate the hatching process as it was deduced that the young would be a more viable source of the cure, rather than their parent who was weak. But the aquarium was not a suitable environment for the eggs to hatch which was built to match the ideal environment for an adult Sea Emperor Leviathan, which differ from the ideal conditions for a juvenile Emperor, causing the eggs to go into a form of natural stasis for a seemingly indefinite amount of time, kept alive by the incubator. Six Ion Crystal Pyramids are found here. 


PrisonInt AnteChamber lo


The first room in the Primary Containment Facility. It is huge and roughly octagonal in shape. A large pillar lies in the center of the chamber, which is used to create Large Ion Crystal Deposits. Around this pillar are cases containing the Alien Relics, six on each side. There are six doorways around the side walls of the Antechamber, four leading to teleporter rooms the other two leading to the "Pipe Room" and "Egg Room". Above the entrance another doorway can be found and accessed by ramps on either side of the entrance, this door leads to the "Baby Experiment Lab". At the far end of the Antechamber is another door that leads to the Moonpool Room. The Antechamber also has many specimen cases containing artifacts the Precursors collected, most originating from other alien races.


A collection of eleven relics is kept in the Primary Containment Facility one of human origin, some of Precursor origin but most from other, unidentified alien species. Further information on these relics can be found here: Alien Relics.

Moonpool Room

A large room accessed through a door at the far end of the Antechamber, the main point of interest in this room is the large moonpool from which it draws its name. The moonpool leads to an observation platform above the Sea Emperor Leviathan's Aquarium where the player will encounter the Sea Emperor Leviathan for the first time. At the far end of this room is a doorway leading to a teleporter, which links to a teleporter in the Aquarium.



"Sea Emperor's Aquarium"

The main feature of the Primary Containment Facility, a huge aquarium containing the Sea Emperor Leviathan and the five Sea Emperor Leviathan Leviathan Eggs. The Aquarium is teeming with life; schools of fish, coral, grasses and Flora being scattered all around, some parts of the Aquarium resemble the Grand Reef and it also has small cave systems. Many large pillars made from the same material as Precursor Bases can be found running in two lines, parallel to each other in the middle of the Aquarium. Atop these pillars are drillable Ion Crystals, six in total. The Egg Incubator is found in a large hollow in the ground surrounded by small mounds of rock amongst which the Emperor will nestle itself whenever the player gets close to the eggs. There is a teleporter directly behind the Incubator, which goes one-way to the Quarantine Enforcement Platform.

Other Data Bank Entries

Shell Composition: The shell casing is formed from thick layers of carbon-composite, suggesting an extensive gestation period. This leviathan species may give birth just once per century, perhaps just once in their lifetimes.

Shell Casing Incisions: Precise incisions suggest a laser-based tool was used to cut open the egg casing and forcibly remove the fetus inside, prior to full gestation.

Analysis: - Time-pressure to develop a bacterial vaccine may have driven the alien researchers to cut open this egg and remove the fetus for study - It is also possible that, removed from its parent and natural habitat, some vital condition for the infant to hatch naturally was not met

Scans indicate this warp gate has not been active since the facility was abandoned. It likely served as an access point to the surface of the planet. It is much too small for the emperor specimen to pass through, but may accommodate a juvenile specimen.

Background: - Superficial damage to the specimen indicates it was forcibly removed from its egg-casing - The fetus appears to have been terminated for dissection immediately on removal - Cryogenically preserved

Bacterial Vaccine Potential: - Analysis of digestive system enzyme production indicates potential for full vaccination against effects of alien bacterium - However the fetus had not fully completed gestation - internal organ development is insufficient for enzyme production

Analysis: - A healthy infant specimen may be able to produce the enzymes necessary for a full vaccine against the bacterium - Given the specimen's potential, it is unlikely the alien researchers would have forcibly removed it prior to full development if they had discovered any way to hatch it naturally

Recommended Steps: - Unclear

Future Plans

  • The antechamber will contain an airlock and various teleporters to different biomes and the other Precursor Bases - the receivers for these teleporters will be found scattered throughout the world.
  • Various cutscenes and animations will be shown here, ranging from simple Sea Emperor Leviathan swimming animations to a dramatic final reveal involving the Sea Emperor Leviathan eggs.
  • Warpers will warp into the aquarium and attempt to kill the player. 


  • The previous name for the Primary Containment Facility was the Primary Research Facility.