Doom 3 timeline


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"The Dawn of Time"

- In the distant past, the beings that will eventually become demons inhabit Earth. They are later banished to Hell.


- Millennia ago, an ancient civilization exists on Mars. This civilization develops advanced teleportation technology, inadvertently opening portals to Hell in the process and triggering an invasion by demons. The resulting war decimates the Martians, who end the demonic incursion by sacrificing most of their population to create the Soul Cube. The Soul Cube is wielded by a great Martian hero, who successfully drives back the demons at the cost of his own life.

- During the war, the Martians capture what will later be known as "the Artifact," a powerful demonic weapon that also functions as a permanent gateway between our dimension and Hell. Realizing the danger that the Artifact poses, yet lacking the ability to destroy it, the Martians seal it away in a hidden chamber at what will eventually become Site 1.

- When the war ends, the surviving Martians use teleporters to evacuate from Mars and relocate to the other inner planets of the solar system, including Earth. Before departing their ruined world, they first entomb their fallen hero in a holy burial site. Buried with him are the Soul Cube and stone tablets engraved with an account of the battle against the demons, intended to warn anyone who might find them against the creation of teleportation technology and prevent another attack from Hell.


- Business magnate Thomas Kelliher founds the Union Aerospace Corporation to further his personal interest in space exploration. At the time, the UAC is a branch of Kelliher's corporate conglomerate, Union Media, which provides the capital necessary to finance the UAC's operations. The UAC initially focuses its attention on weapon and defense contracts, gaining a foothold in the aerospace industry by providing financial bailouts to floundering legacy aerospace companies.


- The UAC mounts the Joint Mars Expeditions. These missions are of historic importance and make the UAC a recognized name in space exploration. In the decades that follow, the UAC expands its reach into various diverse fields of research, including biology, energy, and other scientific fields.

- At some point over the next century, corporate leadership of the UAC passes from Thomas Kelliher to his son, Ian.


October 29

- Construction of the Alpha Labs begins at the UAC's research installation on Mars.


- Excavation of the Martian surface uncovers the Martian hero's burial chamber and leads to the discovery of both the Soul Cube and the stone tablets, although at the time, UAC researchers do not understand the full significance of what they have found. This dig site will later be developed into Site 3.


- Excavation at Site 1, at what will later become the Erebus Facility, uncovers more complex Martian relics, including additional tablets, chambers and tunnels covered in Martian glyphs, and the original Martian teleporter. These archaeological finds firmly establish the existence of an advanced ancient civilization on Mars. Over the following years, UAC researchers study the teleporter, the tablets, and the glyphs in an attempt to reverse-engineer teleportation technology.

- During the next 30 years, archaeologists working at Site 1 uncover the Primitive, a small, intact tablet that both describes the properties of the Artifact and also serves as a cipher key for decoding and translating the other Martian tablets. However, UAC researchers do not recognize the true purpose of the Primitive, and it is sent to the Erebus Facility for storage.


July 17

- The Alpha Labs become fully operational. The Erebus Facility gradually falls into disuse as the Alpha Labs take over as the UAC's primary scientific research facilities on Mars, but work continues at Site 1, the largest of the Martian archaeological dig sites.


- Delta Labs conducts experiments involving the UAC's prototype teleporter. These first-generation teleporter trials, code-named Project Mercury, deal with teleporting small quantities of matter across short distances. Test subjects include small animals and chimps.

~ 2139 - 2143

- Project Mercury experiments produce anomalous results; in theory, the teleportation process should be instantaneous, but in practice, a variable delay occurs before test subjects rematerialize. A robotic probe deployed to determine the cause of the delay finds that teleported matter is first sent through another, intermediary dimension. Video footage from the probe shows multiple sets of eyes observing it as it is being teleported, proving that this parallel dimension is inhabited by non-human life.

- UAC research director Malcolm Betruger requests volunteers from the UAC security forces for expeditions to capture extra-dimensional life-forms. To gain clearance to conduct human teleportation trials, Betruger's assistant, Ian McCormick, falsifies medical records to indicate that researchers have already conducted live tissue experiments. Second-generation teleporter experiments involving human test subjects, code-named Project Gemini, commence in Delta Labs Sector 3.

- The side-effects of teleportation upon human beings are witnessed for the first time. Participants report experiencing nightmarish visions and sightings of strange creatures. Exposure to the other dimension (i.e., Hell) results in a large majority of test subjects developing paranoid delusions, violent behavior, and other signs of mental illness; physical changes include pale skin, slack musculature, and translucent bones, teeth, and fingernails. Ian McCormick reports that the third human test subject to be sent through the teleporter is rendered clinically insane by the experience and is chewing off his own fingers when he reappears on the teleport pad.


- Under Betruger's direction, third-generation teleporter trials, code-named Project Apollo, commence in Delta Labs Sector 4. This involves the construction of a room-sized teleporter capable of sending small teams on extra-planar excursions. Teams are sent through the portal roughly once every two days; upon arrival in the other dimension, they begin exploring the terrain, sending out mapping droids, and setting up research outposts.

- UAC personnel begin capturing extra-dimensional beings for study, suffering heavy casualties in the process. Officially, the UAC treats these specimens as alien life-forms, but the grotesque nature of the creatures, combined with the disturbing eyewitness accounts of the parallel dimension, lead some researchers, including McCormick, to conclude that the other dimension is, in fact, Hell, and their captive specimens are actually demons. To house these specimens, the "demon museum" storage facility is constructed in Delta Labs.

- Around this time, Betruger is contacted through his dreams by demons who offer him great power in exchange for a way to escape from Hell and reclaim Earth. Afterward, Betruger devotes all of his time and energy to teleportation research, searching for a way to break the demons out of Hell and satisfy his part of the infernal bargain. Outside observers, who are unaware of Betruger's pact with the demons, will later describe him as being "obsessed" with his study of both the parallel dimension and the ancient Martian civilization.

- Betruger embarks on an unscheduled trip through the Project Apollo teleporter, entering Hell alone. According to Ian McCormick, when Betruger returns, he is somehow different; he looks and sounds like the same man, but something about his personality has changed.

January 15

- UAC personnel capture an Imp for study. Its left arm is later amputated in order to determine how it is able to throw fireballs; the remaining portion of the specimen is preserved in the "demon museum" in Delta Labs.

February 5

- UAC personnel capture a Hell knight for study. Its head and spinal column are later removed and preserved in the "demon museum" in Delta Labs.

November 2

- UAC researchers preserve the torso and severed head of a Zombie for study. Its partial remains are kept in the "demon museum" in Delta Labs.


- By this year, the UAC is recognized as the largest corporate entity in existence. The company's power and influence are so great that it commands virtually unlimited financial resources and effectively operates above the law, controlling the most advanced technology ever developed by mankind.

- Hell's influence causes paranormal activity to manifest in the Mars facility. UAC personnel across the base report strange and bizarre occurrences, such as hearing unexplained voices or witnessing inexplicable, often fatal equipment malfunctions. Feelings of paranoia and outbreaks of random violence grow more common among base personnel, and several people go missing. Security breaches and reported thefts of weapons and other supplies become frequent.

- The teleportation experiments in Delta Labs place a heavy strain on the Mars base power grid, resulting in electrical fluctuations and power outages throughout the rest of the base. The classified nature of the experiments being conducted in Delta leads to rumors and rampant speculation among base personnel about exactly what kind of work is being done there.

- Betruger grows frustrated with delays in teleportation research. The Project Apollo teleporter can only be activated for short periods of time, just long enough to send through a few people or small pieces of equipment. To solve this problem, Betruger orders the construction of a larger, more powerful teleporter at Exis Labs, one comparable in scale to the Martian original. This is ostensibly for the purpose of teleporting bigger pieces of equipment, such as dropships, but in truth, Betruger plans to use the larger teleporter to transport entire armies of demons out of Hell. His impatience leads him to order that the teleporter be built while the Exis Labs facilities are still under construction; a secondary teleporter is also built at one of the UAC's research outposts in Hell, designed to link up with the portal at Exis.

- As deaths, accidents, and unexplainable occurrences continue to mount, discontent grows among the Mars base personnel, with more workers complaining about unsafe conditions or requesting transfers off-world. Elizabeth McNeil lodges a formal complaint with the UAC board of directors, requesting an official inquiry into the strange events on Mars.

- Richard Meyers begins to investigate the rumors he has heard regarding the experiments being conducted at Delta Labs. He hacks into Betruger's personal logs, believing that he has avoided detection in doing so. Betruger's logs detail his interest in black magic and the occult; the more recent entries reveal his contacts with the demons through his dreams. Meyers is frightened by what he reads, but he does not yet realize what Betruger is planning.


- At least as early as this month, Delta Labs conducts an outreach program soliciting volunteers from among the Mars base's civilian personnel. Volunteers are sought in the areas of teleportation, medical research, and specimen handling, supposedly in support positions; in reality, they will be used as test subjects. At the time, interest in the program is so strong that Delta Labs receives a surplus of volunteers.

July 12

- UAC personnel capture an imp for study. The intact specimen is preserved in the "demon museum" in Delta Labs.

August 6

- Simon Garlick, a Delta Labs research specialist, is appointed for Expedition 14A-2. The goal of the mission is to find and capture another Hell Knight by non-lethal means.

August 8

- During the Expedition 14A-2 in Hell, Simon Garlick records an audio log and notes that he got separated from the rest of his team while taking samples. Unable to contact anyone through the communication links, he opts to try and find his companions.

August 10

- Simon Garlick finds the rest of his team slaughtered. He records his experience through the PDA and considers the possibility that demons have saved him for last and are just toying with him, but the audio log is cut off at the end. It's likely that Garlick is killed immediately afterwards.

September 14

- Andrew Chin complains that UAC security are harassing members of his research staff by asking them inappropriate questions and subjecting them to unnecessary background checks. Chin suggests that if the UAC is concerned about a security threat, they should start by checking their own staff.

September 23

- The UAC board of directors, frustrated with Betruger's focus on extra-dimensional research at the expense of commercializing teleportation technology, seek to rein him in. They unanimously approve Elizabeth McNeil's request to conduct a full operational review of the Mars base, appointing Elliot Swann to serve as their official representative during the process.

September 24

- James Holiday attributes the UAC board's decision to conduct a formal inquiry to ongoing problems related to the transportation of artifacts from Site 3; as Holiday is recording his audio log, his PDA malfunctions, preventing him from elaborating further.

September 27

- UAC personnel capture a revenant for study. The intact specimen is preserved in the "demon museum" in Delta Labs.

October 1

- The first teleportation experiments using civilian volunteers are conducted, involving a group of anesthetized test subjects. The volunteers suffer no immediate ill effects from being teleported, with the exception of one subject who reappears on the teleport pad with several lacerations. Researchers theorize that the wounds are self-inflicted, but are unable to explain how they occurred during the teleportation process.

October 2

- Elliot Swann informs Elizabeth McNeil (and, presumably, Malcolm Betruger) of the UAC board's approval of her request for an official inquiry into the situation on Mars, and that he will soon be leaving Earth to conduct his investigation. McNeil responds that she is pleased to know that corrective action is being taken, but she also tells Swann that Betruger has reassigned her to a research post on Earth, probably in retaliation for her whistleblowing activities. McNeil is disappointed by the transfer, but admits that she fears for both her safety and her sanity if she were to remain on Mars.

- Betruger sends an email to William Banks demanding that all crates containing "religious artifacts" arriving from Earth be transported directly to Delta Labs without delay, bypassing normal shipping procedures.

October 3

- In a terse message to Swann, Betruger dismisses the need for an operational review of the base facilities, telling Swann not to waste his time by coming to Mars.

October 5

- William Banks complains that Betruger's optimizations to the Mars base power grid have been causing malfunctions and power outages in non-critical systems throughout the facility. He intends to file a report with Central Authority on the subject.

October 12

- Peter Raleigh observes that the teleportation test subjects have become increasingly delusional and that all are reporting supernatural experiences. Raleigh notes that while such hallucinations are a common symptom of schizophrenia, he has never seen the same psychosis affect all of the subjects in a controlled test group. He recommends that further experiments be halted until the cause of the test subjects' symptoms can be determined.

October 13

- At the Exis surface tunnel, a construction worker Bill Sanders is forcibly restrained after trying to attack his manager with a pickaxe in a crazed fit, not remembering anything about the incident during the subsequent questioning.

October 18

- Frank Delahue notes that due to increased power demands from the Delta Labs, the Mars base power grid is operating at 23% over nominal capacity. Delahue orders his staff to work in 12-hour shifts to keep up with demand and warns that critical systems will begin to fail if the elevated power levels are not decreased; he also states that if conditions do not improve, "all hell is going to break loose."

- UAC psychologist Dr. Hooper interviews Steve Jensen, who has been exhibiting signs of paranoid psychosis over the preceding weeks.

October 19

- Grant Baston notes an unusually high number of reports of "unexplainable things." He does not elaborate, but mentions frequent power fluctuations and outages, hearing rumors about the experiments in Delta Labs, and says that his staff are both frightened and shorthanded, with workers calling in sick almost every day.

October 20

- William Banks comments on the "alarming number" of missing personnel throughout the Mars base, as well as the unusual number of people who have reported to the infirmary with symptoms of schizophrenia and other psychological problems.

October 21

- Follow-up interview between Dr. Hooper and Steve Jensen. Jensen's condition has deteriorated significantly since the earlier October 18 interview; he is largely unresponsive and has to be restrained.

October 24

- Frank Delahue notes that valve overloads in the main energy processor at Mars City are resulting in dangerous fires; fortunately, due to the rapid response of the engineering team, only one injury as a result of valve failures has been reported.

- Alpha Labs benefits analyst Jack Smith reports a high number of accident reports being filed by UAC researchers and equipment breakdowns happening on a daily basis, with five accidents in the last week alone. Smith describes the case of John Hughes, who was performing maintenance on a plastic extrusion system. According to Hughes, the machine was unplugged from its power source and he had the safety key in his pocket, but it somehow activated itself and "shredded" his arm up to the elbow before someone helped him out of it; Smith reports that the machine is, in fact, still running, and cannot be shut down.

- Henry Nelson reports hearing strange voices in Alpha Labs and notes that several of his employees have had similar experiences, even discussing "ghosts." The same day, Jeff Dickens, a member of Nelson's staff, informs Nelson that he has not slept for three days and has had difficulty concentrating on work. Dickens also mentions that the other staff have felt uneasy since "Hal's accident," although the nature of this accident is not described. Nelson requests that a security team make a sweep of the EFR area.

October 25

- Around this date, Private Swensen, a Marine stationed in the EnPro Plant, commits suicide. According to eyewitness accounts, Swensen, who had been "losing it" and exhibiting signs of mental instability, became agitated when a vending machine refused to accept his credits. Swensen began swearing violently, shot up the vending machine with his plasma gun, and then turned the weapon on himself, vaporizing his own head. In response to this incident, the EnPro service technicians decide to lock up all of the unsecured plasma rounds they can find.

October 26

- Henry Nelson emails Michael Abrams to request additional security in Alpha Labs, saying that his staff have reported hearing voices in the area.

October 27

- Steve Jensen and four other members of the UAC Darklight Armored Corps return from an expedition to Hell. The other members of the squad subsequently die of injuries sustained during the mission, leaving Jensen as the sole survivor of his unit.

October 29

- Peter Raleigh sends out a fresh request for volunteers through the Delta Labs outreach program. He specifically instructs his subordinates to screen volunteers for friends and family members to ensure that they "won't be missed" and that the UAC will avoid further litigation.

October 30

- Bill Tyson reports that troop morale among the Marines stationed at the Mars base has begun to drop, something that he attributes to the UAC's ongoing experiments. He also observes the unusual number of missing people among the base's civilian personnel. To address the situation, Tyson recommends bringing in new Marines on shorter troop rotations. In a separate report, Tyson makes note of the large number of security breaches and the "general feelings of ill will" around the base.

- IT security specialist Paul Simons reports a computer network intrusion. According to Simons, network security was breached several times over the preceding days, and the intrusion may have been taking place over a longer period of time, but the hack was expertly done, with the responsible party skillfully covering their tracks. Simons is able to determine only that the hack originated from somewhere within Delta Labs, and that the culprit had access to all personnel data, including medical reports. The hacker is never identified, but may have been Richard Meyers.

- Manifest controller Marcus Stanton files an audio report in which he complains that cargo is being shipped in and out of Mars City, including to Delta Labs, without his express authorization.

- Mark Caseon reports that 10% of Mars base personnel have displayed symptoms of psychological issues and estimates that, due to underreporting, the real number may be as high as 40%. Caseon notes that even Mars City medical staff are being affected, with several doctors and nurses unavailable to work. He plans to request additional psychiatrists from Earth, as the two existing psychiatrists on staff are overworked and are reporting disturbing content in their patients' sessions.

- Steve Hammer files an audio log describing the circumstances of Private Swensen's death.

November 1

- Steve Jensen dies of a self-inflicted gunshot wound. By this time, his mental condition had deteriorated to full-blown dementia, and he had begun screaming in multiple languages, including Aramaic, about "demon hordes" feasting on the souls of base personnel. Peter Raleigh is so unnerved by this incident that he begins stocking weapons in his office at the Delta Labs.

- David Carter inspects the reactor chamber in Alpha Labs Sector 4 at Larry Kaczynski's request. Carter finds no problems, but reports hearing whispering inside the reactor chamber.

- Paul Raad, chief technical officer for the EnPro plant, reports on the importance of adhering to safety regulations and changing the filters in EnPro's coolant system on schedule. Raad warns that the coolant system is fragile and that even a minor disruption could potentially damage one of the coolant rods, overheating EnPro's reactor core and resulting in the destruction of the entire facility.

- Mark Lamia, an operations coordinator, notes an unusual level of incompetence among his subordinates.

November 2

- After complaining of nausea and insomnia, Jonathan Wills is admitted to the Mars City infirmary, where he attacks Mark Caseon with a stolen scalpel. With the assistance of an orderly, Caseon is able to subdue and sedate Wills. Wills is heavily medicated and left unattended for 20 minutes, during which time he carves three symbols into his arm and cuts his own tongue in half.

- Peter Raleigh files a medical report regarding the death of Steve Jensen in which he details the content of Jensen's earlier interviews.

- A teleportation test subject attacks a non-UAC inspector who is touring the Delta Labs. The test subject in question is "retired" and the remaining test subjects are quarantined in the empty offices in Delta Labs Sector 2 for further observation.

- PFC Hagar sends an email to Bill Tyson in which he reports witnessing a partially assembled sentry bot attempt to fire upon a Marine; fortunately, the sentry bot's ammunition had not yet been loaded. Hagar offhandedly mentions the occasional report of base personnel "going a little crazy."

- Central IT Security runs a diagnostic on Paul Simons's computer network but are unable to detect any problems. They inform Simons that other IT managers have reported intrusions into their own networks, and that the person responsible must either be highly skilled, or possess a "very high level security clearance."

- In an email to Theresa Chasar, Lloyd Renstrom notes that frequent accidents on the Mars base have resulted in tightened security.

November 3

- Paul Raad notes the high number of "stress-related illnesses" spreading through base personnel and reports that EnPro engineer Patrick Thomas was nearly shot by a malfunctioning sentry bot that refused his security clearance. A maintenance team smashed the sentry with a wrench before it could do any harm, but Raad says that Thomas was left traumatized by the experience and may never go near a sentry bot again.

- Nasir Adil, the security chief of Exis Labs, notes a couple of cases of unusual violence among Exis staff. To ensure safety, he files a request for more security personnel in the facility and resupplies one of the security lockers with medical supplies.

November 6

- During a small beer party in Mars City Underground, a technician named Jenny Lin abruptly breaks into a supply cabinet containing an emergency weapon. She then proceeds to kill two security guards and injure another before being killed herself.

November 8

- Matthew White notifies William Banks that research assistant Eric Raffel has gone missing after not reporting for work the entire week, and that no one has seen him in several days.

November 9

- Teleportation test subjects show further signs of mental deterioration; one of them never stops screaming. Peter Raleigh begins to question his safety and requests that a security guard be posted on-site, with instructions that the quarantined offices in Delta Labs Sector 2 be kept locked at all times.

- Jordan Kenedy, a doctor based on Earth, emails Mark Caseon to let him know that additional medical staff and resources for Mars City may not be available, and that he could be "on his own" for a while. At some point over the next week, Caseon decides to leave Mars entirely; his transport is scheduled to leave on November 15.

- Matthew Gaiser informs Delta Labs security team member Karl Cullen that a "large specimen" will be sedated and transported via the Monorail system from Delta to Phobos Labs. Gaiser requests a security detachment outfitted with full body armor and plasma guns to accompany the transport, noting that the specimen is "hazardous" and that seven men died during the attempt to capture it alive.

November 10

- Maintenance technician Adam Berneche reports hearing strange whispers while working on the heat shields in Mars City.

- Master Sergeant Thomas Kelly, commanding officer of the Marines stationed at the Mars base, informs Bill Tyson that a new Marine transfer is en route from Earth to replace Allen, another Marine.

- Human resources director Kellsie Krisch approves Michael Abrams's request for additional security in Delta Labs, remarking that "Gormen's" death was tragic; she does not describe the circumstances of Gormen's death.

- A maintenance technician Bob Thompson writes a message to his co-worker Phil Anders where he accuses UAC of trying to cover Jennifer Lin's death up and hopes to try and make something about it to avenge her.

November 11

- In response to Jack Smith's benefits report detailing the high number of accidents among UAC science personnel, safety coordinator Brian Jenkins recommends the implementation of a "buddy system" in Alpha Labs in order to improve workplace safety and decrease the number of accident reports being filed.

November 12

- Frank Delahue informs UAC Security of airlock malfunctions in the Mars City Underground. He also describes increased tension among base personnel over the preceding weeks, mentioning more "angst" and a noticeable change in the personalities of once-friendly co-workers.

- Kyle Berger files an audio log related to a fatal accident that took place the previous week, in which research assistant Roy Patterson was killed while calibrating the Elemental Phase Deconstructor. Witnesses reported that Patterson appeared to "see something" in the calibration chamber; this caused him to back up into the particle beam, which then blew off the back of his head. Witnesses report that afterward, Patterson's eyes rolled back and forth and that he attempted to speak, but Berger opines that after losing that much brain matter, it was probably just "reflex actions."

- Nasir Adil records an audio log where he expresses his concern over the incoming visit from Swann and notes half the weapons stationed in the lockers across Exis Labs had been stolen.

November 13

- In an email to Jack Smith, Ari Braden mocks Brian Jenkins's suggestion regarding a "buddy system," describing a grisly accident involving Joe "TorsoBoy" Moss. According to Braden, the Albuquerck Capacitator in Alpha Labs "growled" and engaged without being connected to a power source, dismembering Moss and setting his hair on fire, forcing his co-workers to run for water with which to put him out.

November 14

- Ray Gerhardt sends an email to several co-workers in which he announces that he will be leaving both Mars and the UAC upon the completion of one final assignment in Delta Labs the following day. He invites interested parties to join him for a farewell drink in the Mars City kitchen on that day and notes that his shuttle is scheduled to leave early on November 16.

November 15 - Doom 3 Begins

- One of the teleportation test subjects is moved to the medical bay following repeated instances of self-mutilation. Peter Raleigh clears the subject for disposal, as it is no longer useful for research purposes.

- In an email to Mark Caseon, Sarah Holsten claims that 'Zach', a worker in Operations, has been exhibiting erratic behavior and tried to bite her earlier in the day.

- Duncan Mathews reports having difficulty sleeping and working. He emails a request to UAC Security for both security armor and a plasma gun. The request for armor is granted; however, because Mathews is a civilian and is not allowed to possess weapons, his request for a plasma gun is denied.

- Having realized the danger posed by the ongoing teleportation experiments in Delta Labs, researcher Jonathan Ishii makes an unauthorized trip to the decommissioned Mars City communications array in order to send an emergency message regarding the true nature of Betruger's work. Ishii is reported missing later that day, and UAC security sends out an alert asking base personnel to be on the lookout for him.

- At 06:18 Mars Standard Time, Phantom-class Dropship T4409, callsign Darkstar, arrives at Mars City. Aboard the transport are three passengers: Elliot Swann, his bodyguard Jack Campbell, and the new Marine transfer. Darkstar begins to refuel and is scheduled to depart for Earth twelve hours later, but may have left the base before that time.

- Betruger, Swann, and Campbell hold a tense meeting in which Swann demands full access to the entire Mars base in order to conduct his operational review of the facility, including the classified projects at Delta Labs. Betruger regards Swann with hostility, promising him that "amazing things" will soon happen at the base.

- During a conversation in the Mars City cafeteria, Marines K. Miller and M. Marak mention that Cpl. Allen, the Marine whom the new transfer is replacing, "lost it" and was shipped back to Earth earlier in the week.

- The Marine transfer reports for duty to Sergeant Kelly. Kelly dispatches the Marine to the Mars City communications array to locate and retrieve Jonathan Ishii, who was last seen in that area.

- Circumstances force Betruger to act. With the large-scale teleporter at Exis Labs still under construction, UAC researchers on the verge of discovering the Soul Cube's true purpose, and Swann having arrived on Mars to conduct an audit of all ongoing experiments, Betruger's plans are in jeopardy. Unable to wait any longer, he retrieves the Soul Cube from Delta Labs and takes it through the Apollo teleporter into Hell, depriving humanity of its greatest weapon against the demons.

- Moments after Betruger steps through the teleporter, its protective stabilizers immediately fail. At approximately 07:00 Mars Standard Time, the demonic invasion of Mars begins.

- A shockwave of hellish energy radiates outward from the Apollo teleporter in Delta Labs and sweeps across the entire Mars base, causing catastrophic structural damage. Demons begin pouring out of the portal, swiftly overwhelming the base's Marine defenders. The overwhelming majority of base personnel are either killed by demons or turned into zombies, with a casualty rate of at least 90 percent among the civilian staff. Survivors of the initial attack include Campbell, Swann, Sergeant Kelly, and the Marine transfer; Jonathan Ishii becomes a zombie, forcing the Marine transfer to kill him. Afterwards, while fighting his way back to the security checkpoint, the Marine transfer engages and kills several zombified staff members, including those whom he met just before the invasion happened, along with several Imps.

- The EnPro Plant chief technician Allen Rhodes records a personal update, where he notes the situation in EnPro Sector 1 deteriorating rapidly. After the communication channel goes down and several of his staff fail to report back, he and the rest of his team barricade in the control room while attempting to contact Richard Meyers. Not long afterwards, they all attacked and slaughtered by demons.

- Sergeant Kelly orders all surviving Marine units to fall back to Marine Command in Mars City to mount a defense against the invaders. With the monorail track between Mars City and the Delta Labs having been destroyed in the attack, Kelly remains in Delta Central Authority to coordinate between the remaining Marine teams.

- The Marine transfer makes his way to Mars City, only to find it overrun and ransacked by demons. After arriving at the Marine HQ, he receives an order from Sergeant Kelly to rendezvous with Bravo Team, who are en route to the main Mars communication facility in order to send a distress call to the orbital fleet. Meanwhile, Campbell and Swann begin heading toward the same location in order to shut down all off-world communications and prevent the demonic invasion from spreading beyond Mars.

- During a trip in the Administration sector of Mars City, the Marine overhears Swann trying to take control of the situation from Dr. Betruger. After the attempt fails, Campbell decides to execute "plan B" and uncases his BFG. Both Sergeant Kelly and The Marine transfer note Hell flesh growing all around the base.

- Six hours after the demonic invasion begins (around 13:00 Mars Standard Time), Bravo Team is ambushed by demons while navigating through the EnPro Plant. During the resulting firefight, stray bullets damage the plant's coolant system, destroying a coolant rod and causing the reactor core to begin overheating. All members of Bravo Team are killed except for a single unconscious survivor who is dragged away by demons to another part of EnPro, presumably to be killed or eaten later. Another member of the team survives, keeping the transmission card with him. He gives the card to the Marine transfer after finally meeting him, only to get killed by a Wraith immediately afterwards.