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Scans indicate this structure is composed of a metal alloy with unprecedented integrity. No matches found in database. Performing structural analysis.

― PDA, Dialogue


The Quarantine Enforcement Platform is a massive Alien weapon system that is located on the Mountain Island. It is the source of the energy beam responsible for causing the Degasi, the Aurora, and the Mercury II to crash on Planet 4546B, as well as destroying the Sunbeam during its rescue attempt.

The Quarantine Enforcement Platform was built by the Precursor Race around one thousand years ago, in order to contain the Kharaa Bacterium. Near one of the entrances, an Alien Arch connecting to the Primary Containment Facility can be found. There is only one Quarantine Enforcement Platform on the entirety of Planet 4546B as its beam can bend around the planet to strike ships on the other side. The main section of the structure stretches from 20 meters above the surface to 130 meters below it, with the cannon adding an additional 110 meters to its height even in its resting state.

The player must locate a Purple Tablet to gain entrance to the Quarantine Enforcement Platform without using the moonpool; several of them are located on the island, one of them located inside the facility itself on the balcony near the barrier to the control room, and one is located in an underwater cave near the base. Another purple tablet can be found above the entrance of the Quarantine Enforcement Platform. The player must cure themselves of the Kharaa Bacterium before being able to disable the Quarantine Enforcement Platform and leave the planet. If the player attempts to disable the facility before they cure themselves of the Kharaa Bacterium, they will be denied.

An abundance of Warpers can be found patrolling in the waters around the Quarantine Enforcement Platform.

Three Ion Cubes can be found here, as well as two scannable Alien Relics, the Doomsday Device, and the Alien Rifle. These relics are protected by indestructible cases made by the Precursors, and thus are inaccessible to the player.


The Quarantine Enforcement Platform's interior consists of two major areas, the upper 'engineering' section, and the submerged lower section. Both sections have separate entrances, although the player can take an anti-gravity elevator found within the facility in order to access one section from the other. The purple Alien Tablet is required in order to unlock the upper entrance and the control room.

Upper Section[]

The entrance to the upper section can be found on the beach of the Mountain Island, a large door gives access to the interior from here. Two data terminals and two Ion Cubes are found in the upper section. The Quarantine Enforcement Platform itself, when on standby, is placed vertically as to not immediately alert the player to the fact that it is actually a superweapon, instead appearing as some kind of tower-like monument.

Lower Section[]

The entrance to the lower section is a large opening in the side of the "tower", which gives access to a large moonpool. The moonpool is large enough to fit two Cyclops submersible vehicles. Inside the moonpool room are two doors, one leading to the right and one leading straight forward. The door to the right leads to the elevator, while the other door leads deeper into the facility, into a room dominated by a series of platforms and ramps. Another Ion Cube can be found here.

In the corner of the "ground floor" of the room is a winding hallway that leads to the Arch room, although it cannot be used until its corresponding Principal Alien Arch is activated in the Alien Thermal Plant. Going up the ramps will lead the player to the control room. The deactivation terminal can be found here, which will unfold and activate when the player is near it. After unsuccessfully using the terminal, the player will receive a notification from their PDA about the location of the Disease Research Facility.


When the countdown for the Sunbeam's arrival ends, the player will receive one of two messages from their PDA, depending on their location:

Version 1[]

If the player is present at Mountain Island when the Sunbeam arrives, they will receive this message from their PDA:

Log-128 "Avery Quinn: "Survivor, we see you!' Man, I don't know how you held out down there! We've broken atmosphere and we're descending towards the landing site.
Is that a building down there?! What do you mean you can't identify it?
Hold on, no turning back now.
Positions everyone, touching down in 10, 9, 8- *Static*
It's coming from the building?! Change course set thrusters to full. *Distorted static*

Version 2[]

When the player is not present at Mountain Island during the arrival of the Sunbeam, they will receive this message from their PDA instead:

Log-128 "PDA: Picking up orbital transponder signature of trading vessel Sunbeam. The vessel is approaching the planet's surface and initiating surface scanning procedures. Detecting massive power surge from anomalous contact. Energy discharge detected. Vessel signature lost."

Quarantine Enforcement Platform Terminal[]

Terminal Deactivation Failed[]

This sound plays when the player tries to disable the terminal while he is infected.

Terminal Deactivation Failed Again[]

This sound plays when the player tries to disable the terminal the second time while he is infected.

Quarantine Enforcement Platform Disabled[]

This sound plays when the player successfully disables the terminal.

Terminal Open[]

This audio plays when the player approaches the terminal and it prepares for the player to attempt to disable it.

Terminal Loop[]

This sound loops when the terminal is open.

Data Bank Entries[]

Discovered inside an alien facility, it was not possible to translate any useful information, however scans have returned some information on the device itself.

It is likely a solid-state computer, although there is no clear way to interface with it. On approach it began producing a low-frequency radio wave containing complex but recognizable data patterns.

It is likely the alien species which designed this technology evolved, or genetically selected, sensory apparatus to 'hear' and understand the information being broadcast by the device, and to communicate back. The mental processing power required to perform this kind of telepathy would imply the designers were considerably more psychologically developed than the common human.

Assessment: Further research required

This data set appears to be a multidimensional schematic of some kind. By mapping the pattern to three-dimensional space it is possible to gather a basic understanding of this facility's internal workings.

Construction Material:
The facility's unknown construction material is identified as an ultra-hard, non-reactive metal amalgam, synthesized from offworld materials. There is no indication that it can be damaged or destroyed by available means.

The schematic indicates the facility was to be powered by a separate, self-sustaining power plant, located elsewhere on the planet. The location is not listed, but there is evidence the designers intended to harness the planet's natural thermal energy.

The facility consists of the upper engineering section, where this schematic was found, and the control room, which is accessed via a security-sealed elevator shaft, or a separate underwater moonpool.

The control room in the lower section houses the only known way to interface with the facility, however the schematic does not detail the operation procedure or installed security measures.

This device houses energy equivalent to a 100MT nuclear detonation, which can be channeled through the facility and directed at vessels overhead, or bent around the planet's gravitational pull to strike targets in orbit. Power is routed via the attached terminal, allowing for the device to be deactivated if necessary. It is currently operating without parameters, suggesting it will target any ship within range.

Intercepted background data regarding further alien facilities elsewhere on the planet.

Disease Research Facility
- Depth: 800m
- Location: Cave system with extensive fossil record, south-west of enforcement platform
- Function: Live specimen study
- Objective: Synthesis of antidote for highly infectious bacterium designated 'Kharaa'

Thermal Power Facility
- Depth: 1200m
- Location: Inside an extensive natural rock formation, in an area of intense volcanic activity
- Function: Generate energy for all local facilities

Offsite Laboratory - DATA CORRUPTED
Primary Containment Facility - DATA CORRUPTED

In the event of an outbreak, quarantine procedures will be automatically enforced with immediate effect. The quarantine enforcement platform will target all incoming and outgoing craft, to prevent the spread of infection offworld.


Main article: Achievements
Spoiler alert: The following section contains story related material.
QEPAchievement Ancient Technologies

Find the Enforcement Platform

How to obtain: The player has to reach the Mountain Island and find the Quarantine Enforcement Platform.



  • Previous names for the Quarantine Enforcement Platform were Precursor Gun, Precursor Global Defense System, Precursor Ground-to-Air Weapon System and the Precursor Array.
  • Previous versions of the weapon were positioned in a way where it was more apparent that it was in fact a weapon system. The current version makes this less obvious by having the weapon point straight up prior to firing, appearing like a tower.
  • The three cube-like structures found around the Quarantine Enforcement Platform may be a variant of the Sonic Deterrents found near the Primary Containment Facility. Whether this was intention, or purely coincidence is unknown.
  • In Experimental Update Version 46346, an event commonly referred to as the "Skittles Update" occurred. The game had gone over the limit of textures by the accidental addition of the Quarantine Enforcement Platform model and several other Precursor props to the Entity Gallery. This resulted in the full removal of the Entity Gallery.
  • The PDA states the energy core "houses energy equivalent to a 100MT nuclear detonation." For comparison, the nuclear bombs that destroyed Hiroshima and Nagasaki had explosive payloads of about 15 kilotons (Little Boy) and 20 kilotons (Fat Man); at most, a fiftieth of a percent of the energy core's output. The core's output is still about more than twice the 50-58 megaton payload of the largest nuclear bomb ever detonated, the Tsar Bomba.