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


Translating local alien broadcast... WARNING: Vaccine development program terminated. Emperor egg hatching project terminated. Live specimens terminated. Evacuate immediately.


― PDA, Dialogue


The Primary Containment Facility, also known as the Emperor Containment Facility, Sea Emperor Prison or merely the Prison, is an Alien Base located within the Lava Lakes that serves as the final major story location. It was built by the Precursor Race around one thousand years ago and is home to the last remaining Sea Emperor Leviathan, along with the five remaining Sea Emperor Leviathan Eggs. There are two entrances to the Lava Lakes containing the Primary Containment Facility; located at -300 -1270 -150 and 90 -1240 360, southeast and directly north of the Lava Castle, respectively.

The Primary Containment Facility requires the Blue Tablet to unlock, which is found in the Alien Thermal Plant.

The Primary Containment Facility, like the other Alien Bases, was built a little under one thousand years ago. Five Sonic Deterrent devices can be found in the area around the base, preventing attacks on the facility from the native fauna. It was built to contain the Sea Emperor Leviathan after it was discovered that it was immune to the Kharaa Bacterium. The aquarium section was originally all inorganic with two Alien Arches set up inside, one leading back into the Antechamber's moonpool and another leading to just outside the Quarantine Enforcement Platform. However, as creatures began migrating into it via the Arches, 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. Five of the eggs that the Sea Emperor Leviathan was found with was 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.




The first room in the Primary Containment Facility. It is huge and roughly octagonal in shape. A large pillar, called the Ion Cube Fabricator, lies in the center of the chamber, which is used to create Large Ion Cube 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, the four doors positioned at diagonals lead to Arch rooms, the middle left door leading to the "Pipe Room", and the right to the "Egg Laboratory". Accessed by ramps on either side of the entrance to the facility, another doorway can be seen, this door leads to the "Baby Experiment Lab". At the far end of the Antechamber is another door blocked by a force field that leads to the Moonpool Room, along with its respective Forcefield Control, requiring a Blue Tablet. The Antechamber also has many specimen cases containing artifacts the Precursors collected, most originating from other alien races.



Alien Relics

A collection of eleven relics are kept in the Primary Containment Facility, with 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.

Egg Laboratory


Egg Laboratory

(for images see gallery) This laboratory is accessed through the middle door on the right side of the antechamber. This purpose of this laboratory was to study the hatching processes of local life form's eggs in order to find out how to hatch the Sea Emperor Leviathan eggs. As such, the laboratory contains many eggs from the local life forms, forty-three eggs are kept here in total, including one Sea Emperor Leviathan egg and two Sea Dragon Leviathan eggs.

Pipe Room


Pipe Room

(for images see gallery) Although this room is not huge, the pipes originating from it cover tens of thousands of meters. This room's purpose is to pump cool, oxygen-rich water from the surface biomes into the aquarium, and remove the oxygen-deprived water, maintaining a stable environment for the Sea Emperor Leviathan. This room also contains five small aquariums that are filled with various coral and flora species, these aquariums have pipe exits in them so are presumably for the purpose of enriching the circulating water with plant and coral matter. The Sea Emperor Leviathan using its telepathic abilities trained Peepers to use the pipe system to distribute Enzyme 42 to the surface biomes, keeping a small amount of life on the planet alive.

Dissection Lab


Dissection Lab

(for images see gallery) This small room contains one Sea Emperor Leviathan egg that has been forcibly opened, as well as a dead Sea Emperor Leviathan fetus on a dissection table. Scanning these items reveals that the Precursors were desperate in trying to obtain Enzyme 42 when their attempts to naturally coax the eggs to hatch failed, forcing them to dissect one of the extremely valuable eggs.

Moonpool Room


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, suspended by four cables, where the player will come face to face with the Sea Emperor Leviathan for the first time. At the far end of this room is a platform with an Alien Arch on it, the platform cannot be accessed from the Moonpool Room, only being accessible through an Arch in the Aquarium.

The Moonpool Room cannot be accessed unless the forcefield securing the entrance has been disabled, which can be done using a Blue Tablet at a control, located in the Antechamber.



Sea Emperor's Aquarium

The main feature of the Primary Containment Facility; a huge aquarium containing the Sea Emperor Leviathan and the five remaining Sea Emperor 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. There are also small cave systems, one containing a pair of Oculus, the only place they are found other than the Jellyshroom Caves . Large pillars made from the same material as Alien Bases can be found running in two lines, parallel to each other in the middle of the Aquarium, topped with larger, green, rectangular lights. Aggressive creatures, such as Stalkers, Bonesharks, and Cave Crawlers, will be passive to the player and are thus not a threat. Players can safely ride their Seamoth around the aquarium regardless of depth limit. Two Ion Cubes can be found here, one on a pedestal near the Arch at the back of the Aquarium, and another located in a cavern system having seemingly been abandoned during the evacuation of Precursors.

Pipe System


Pipe System

Eight Alien Vent Entrance Points are located in the aquarium, which pumps oxygen-rich water into the aquarium to keep a stable environment. Peepers use these vents to travel to and from the surface carrying Enzyme 42.

Incubator Device


Incubator Device

The Incubator Device is found in a large hollow in the ground surrounded by small mounds of rock amongst which the Emperor will nestle itself when the player gets close to the eggs. There is an Arch directly behind the Incubator, which connects to an Arch near the Quarantine Enforcement Platform. The eggs can be hatched using Hatching Enzymes.

Other Data Bank Entries

This device appears to be the origin of the raw mineral that forms the base of the ion cubes which power smaller alien systems. Likely drawing power itself from the main thermal plant, this device may represent an almost limitless source of energy.

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.


  • 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 arch 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 should accommodate smaller organisms.

This fetus matches available biological data for the sea emperor leviathan. It was likely a child of the adult specimen contained within this facility.


  • Superficial damage to the specimen indicates it was artificially removed from its egg-casing
  • Stunted tissue development suggests the organism expired during the removal process
  • Tissue samples have been taken from the digestive tract


  • It appears the aliens were attempting to formulate a cure for the bacterium from enzymes produced in this specimen's digestive system
  • Without a young, healthy specimen these efforts were in vain

While all other creatures encountered within the facility are isolated here, peepers appear to be coming and going of their own accord via the alien pipe network. They are exhibiting behaviour unseen anywhere else on 4546B.

  • On arrival, peepers are approaching the sea emperor
  • Peepers exhibit a natural affinity for the stomach enzymes being expelled by the emperor
  • Peepers which have come into contact with the enzyme are returning to the pipe network


  • This behavior must be the source of Enzyme 42 on 4546B, or the area thereof which supports life
  • It is likely also responsible for the survival of the emperor and the other lifeforms contained within the facility

Scans indicate the egg is in a healthy condition of self-regulated stasis.

  • Microscopic holes have been bored into the shell
  • Trace volumes of artificial chemicals have been detected
  • It is possible fluid samples have been taken from this specimen, or that research substances have been injected in a vain effort to trigger a hatching response



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