Primary Containment 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 in Subnautica. Built by the Precursor Race approximately one thousand years ago, it houses the last remaining Sea Emperor Leviathan and five of her eggs.

Overview

The facility was constructed to contain the Sea Emperor Leviathan after it was discovered that she was immune to the Kharaa Bacterium. The Precursors hoped to extract Enzyme 42 from her or her offspring to create a cure for the infection devastating other life forms on Planet 4546B.

There are two entrances to the Lava Lakes leading to the facility:

• Coordinates: -300 -1270 -150 (Southeast)
• Coordinates: 90 -1240 360 (Directly north of the Lava Castle)

Accessing the facility requires a Blue Tablet, found in the Alien Thermal Plant. An additional Blue Tablet is needed to access the Moonpool and view the Sea Emperor directly. Five Sonic Deterrent devices surround the area to prevent attacks from native fauna.

The aquarium section was originally inorganic but evolved into a thriving ecosystem due to flora seeds and mud brought in by creatures migrating through Alien Arches. The Sea Emperor Leviathan at the center helps maintain this balance. Five eggs were placed in an Incubator Device to stimulate hatching, as juvenile leviathans were deduced to be a more viable source of the cure than the weakened adult.

Areas

Antechamber

The first room in the facility is huge and roughly octagonal. In the center lies the Ion Cube Fabricator, a large pillar used to create Large Ion Cube Deposits. When depleted, the pillar rises, fabricates a new deposit over two minutes, and lowers again.

Surrounding the pillar are cases containing Alien Relics collected by the Precursors from various species. There are six doorways around the sidewalls:

• Four diagonal doors lead to Arch rooms.
• The middle-left door leads to the Pipe Room.
• The right door leads to the Egg Laboratory.
• A ramped doorway leads to the Dissection Lab.
• At the far end, a force-field blocked door leads to the Moonpool Room, requiring a Blue Tablet to disable.

Alien Relics

Eleven relics are kept here, including one of human origin, some Precursor-made, and most from unidentified alien species. These artifacts provide lore about other civilizations encountered or referenced in the game.

Egg Laboratory

Accessed via the middle door on the right side of the Antechamber, this lab was designed to study egg hatching processes. It contains forty-three eggs in total, including:

• One Sea Emperor Leviathan egg
• Two Sea Dragon Leviathan eggs
• Unimplemented Shuttlebug egg
• Unimplemented Reefback egg
• Various local fauna eggs

Pipe Room

Though small, the pipes originating here span tens of thousands of meters. Their purpose is to pump cool, oxygen-rich water from surface biomes into the Aquarium while removing oxygen-deprived water to maintain a stable environment for the Sea Emperor.

Five small aquariums filled with coral and flora species are present, presumably to enrich the circulating water. The Sea Emperor Leviathan trained Peepers using telepathic abilities to use this pipe system to distribute Enzyme 42 to surface biomes, sustaining minimal life on the planet.

Unreachable variants of Flora and Coral can be seen inside these aquariums, including Acid Mushroom, Blue Barnacles, Cave Bush, and others.

Dissection Lab

This small room contains a forcibly opened Sea Emperor Leviathan egg and a dead fetus on a dissection table. Scanning these reveals the desperation of the Precursors; when natural hatching failed, they dissected a valuable egg to attempt extracting Enzyme 42 from the fetus's digestive tract.

Moonpool Room

A large room accessed through the force-field blocked door in the Antechamber. Its main feature is the Moonpool, which leads to an observation platform suspended above the Sea Emperor's Aquarium. This is where the player first encounters the Sea Emperor Leviathan.

At the far end is a platform with an Alien Arch, accessible only from the Aquarium side, not the Moonpool Room itself.

Aquarium

The main feature of the facility is a massive aquarium housing the Sea Emperor Leviathan and her five eggs. The environment is teeming with life, resembling the Grand Reef, with schools of fish, coral, grasses, and flora. Small cave systems exist, one containing Oculus, found nowhere else except the Jellyshroom Caves.

Large pillars made of Alien Base material run parallel through the middle, topped with green rectangular lights. Aggressive creatures like Stalkers, Bonesharks, and Cave Crawlers become passive here. Players can safely ride their Seamoth regardless of depth limits.

Two Ion Cubes can be found here: one on a pedestal near the back Arch, and another in an abandoned cavern system.

Pipe System

Eight Alien Vent Entrance Points are located in the aquarium, pumping oxygen-rich water in. Peepers use these vents to travel to and from the surface carrying Enzyme 42.

Incubator Device

Located in a large hollow surrounded by rock mounds, this device holds the five Sea Emperor Eggs. The Sea Emperor nests here when the player approaches. An Arch behind the incubator connects to the Quarantine Enforcement Platform. The eggs can be hatched using Hatching Enzymes obtained from the Peepers.

Data Bank Entries

Ion Cube Fabricator

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.

Sea Emperor Leviathan Study

According to translated data logs, an indigenous leviathan species was found to produce a unique substance referred to as 'Enzyme 42', which inhibited the symptoms of the kharaa bacterial infection in other indigenous organisms. The specimen was captured and contained in a purpose-built habitat for further study.

The alien researchers went to great lengths to provide for the lifeform's environmental needs, including the import of interdependent flora and fauna via an onsite warpgate, however its health quickly deteriorated.

When quarantine was imposed all warp gates and forcefields were sealed. All attempts to develop the enzyme into a vaccine had been unsuccessful.

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

Dead Fetus Analysis

Found preserved in a display case, it was likely a child of the adult specimen contained within the facility.

Physiology:

• 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

Analysis:

• 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

Water Flow Analysis

Water flowing to and from the primary containment facility is being automatically controlled, independently of other safeguards. Data on the water composition has been recorded:

Inflow: Water is being drawn from different biomes around the surface of the planet. The water temperature is considerably lower than the volcanic environment outside the facility, while micro-organism and nutrient counts are substantially higher.

Outflow: Oxygen-deprived water is being flooded from the system and recycled back to the surface.

Peeper Behavior

The pipes drawing water into the containment facility are filled with peepers arriving from the surface.

• The fish show no signs of distress
• The specimens scanned have all consumed high quantities of seeds and organic matter from the surface
• Some specimens are beginning to show signs of infection

A peeper specimen was observed emitting a faint, fluorescent enzyme trail, and engaging in unusual behavioral patterns.

• Peeper is actively approaching other creatures, including predators
• The spec[ecimen is distributing Enzyme 42]