Hell

Hell is a cornerstone element of the Doom universe. It is the source of the demonic invasion in the games. It has a significant presence in many levels, and is the setting of parts of Doom, Doom II, Final Doom, Doom 64, Doom 3 and Resurrection of Evil.

Overview
Typical features of Hell in these games include copious numbers of mutilated bodies, some apparently still alive and presumably of the damned, and scatterings of Satanic iconography. Most of Hell's levels architecture involves jagged rock walls, fire, inverted crosses, wooden doors, stalagmites, dead trees and lava in place of nukage. Rarely does the player come across natural or technological aspects in the Hell levels, and indeed the structure of the levels themselves do not have any sense of flow or continuity.

In every Doom game, Hell is depicted as having developed biocybernetics or at least have stolen from Earth technology and modified it on their own. Implanting modern and futuristic weapons into many of its demon's body, including powerful demons as the Cyberdemon and the Spiderdemon, which both have mechanical and organic body parts. The Icon of Sin appears to be an enormous, partially mechanical demonic head, though Doom II's endgame text indicates it has a suitably massive body as well.

Inhabitants of Hell
Hell is populated by a wide variety of creatures, from damned souls and zombies to demonic beasts and cybernetic monsters. Not much is known about the exact origins of these creatures. Some of them are likely former humans, while others may have been born (or created) in Hell itself. These creatures are all savage, brutal, and relentless, yet fairly intelligent and able to work together towards a common goal: The conquest of Earth.

In Doom 3 the creatures of Hell are controlled by an entity of great power and malevolence, which refers to Hell's inhabitants as its "children." This nameless entity speaks through Dr. Malcolm Betruger and later manifests itself as the Maledict. It is unknown if this entity is the sole leader of Hell, or just one of the leaders of Hell. In any case, the creatures of Hell obey its every whim.

Demonic possession
Zombies in the original Doom are often regarded as "former" humans possessed by demons from Hell. The Doom Bible states that possession can happen to living but sleeping humans.

In Doom 3 and Resurrection of Evil, it's demonstrated that both dead and living humans can be possessed. Most of the civilian and security personnel on the Mars base are possessed and converted into zombies in the first wave of the demonic invasion. These zombies also lack a soul after a given amount of time, as the Artifact cannot absorb a soul from a downed enemy that was a zombie, although it can take souls from any other bodies and in one instance it can take the soul of a man during the game who becomes a zombie in front of the marine and is killed.

For unspecified reasons, some characters - such as the Marine which the player controls - are not taken over. Counselor Swann, Jack Campbell, Sergeant Kelly, along with a handful of marines and civilians are also amongst those not instantly converted into zombies. Throughout the game, the Marine experiences instances of blurred red vision - usually accompanied by evil laughter or demonic language. Also, early in the game, when the Marine looks into a mirror, he sees a vision of himself starting to turn into a zombie. These incidents are possibly the result of the demons' unsuccessful attempts to possess him. These events, coupled with the fact that quite a few of the base's military personnel were initially unaffected by the demonic invasion, suggests that the demons cannot possess those with strong, well-disciplined minds - or at least have difficulty doing it.

A second process of zombification is also referred to in Doom 3, in which the victim is slowly driven insane by a mysterious ailment. The victim suffers from hallucinations and voices, and becomes increasingly hostile and violent towards those around him. Physical changes occur only at the end stage. It is unknown whether this is caused by a virus or magic. In any case, this insanity can only be contracted by those who have visited Hell.

In the classic Doom novels, where Hell is not a part of the story, it is indicated that only dead humans can be made into zombies, through biotechnology. In the Doom 3 novels, where Hell is part of the story, many of the UAC personal are possessed just like the game, but some zombies grow claws, jaws and demon-like body parts and others are more stronger and faster than the game's zombies.

Access to Hell
In the classic games Hell is discovered following experiments in teleportation technology, and during gameplay Hell is only accessible by long-distance teleporters or gateways. In the original Doom teleporters notably have Satanic symbols on them.

Hell in Doom is heavily based on the religious concept that the souls of bad people spend eternal damnation in Hell after death. This is indicated in the Doom II endgame text, "You wonder where bad folks will go when they die now.", and again in The Plutonia Experiment 's endgame text, "Hell has gone back to pounding bad dead folks instead of good live one". Because one cannot physically travel to Hell without the aid of some sort of gateway, Hell's actual location is never revealed, though it is indicated by the Doom FAQ and by the unusual behavior of the environment in Hell in Doom 3 that it is not a part of our universe but rather another dimension entirely. On the classic games, the only way to get physically out from Hell is killing the leader of the demonic invasion such as the Spiderdemon or the Icon of Sin.

In Doom 3, it transpires that teleporter technology was derived from tablets left behind by an ancient Martian race, which went virtually extinct after a full-scale demon invasion on Mars some point in the distant past. Doom 3 also establishes that the demons can create their own portal - known as the Hell Hole - which the Player must destroy in the final level. In the game, it's also possible to exit from Hell with the possession of the Soul Cube, since the Marine only escapes from there after recovers the artifact. In Resurrection of Evil it is revealed that the demonic Artifact acts as a gateway between Hell and our reality, and upon being awakened, enables the demons to invade Mars again.

Differences between games
While the major Doom games all depict Hell, the theme changes slightly between games. The variations between Doom and Doom II are based mainly on levels created by different designers. Doom 3's Hellish atmosphere departs more strongly from the original games.

Doom
In the storyline approaching the beginning of Doom, military experiments are conducted between the gateways at UAC facilities on Phobos and Deimos. Something went wrong, and "soon afterwards, Deimos simply vanished from the sky." In the original Doom, Mars's moon Deimos provides the first link between out universe and Hell. Deimos's mysterious absence is referred to in Knee-Deep in the Dead 's ending text, after the player steps through the gateway at the end of  E1M8: Phobos Anomaly : "It...looks like the lost Deimos base." It's later revealed at the end of Episode 2, The Shores of Hell, that the entire moon had somehow been transported to Hell, which would no doubt account for the complexes being seemingly warped and taken over by demonic means more so than the Phobos installations. The gateways, still functioning between Phobos and Deimos, provided the first entryway into Hell. The original Doom's Episode 3, Inferno, entirely takes place in Hell, where it is depicted as predominately brimstone-covered with a fiery sky, complete with a demonic cathedral and pools of blood. Walls and floors occasionally appear to be made from body parts including human skulls, intestines, spines and skin. In the PlayStation version of the game, Hell's sky is filled withgreen flames, while the Saturn version's stages have a city skyline. The game's box art and the ending screen for The Shores of Hell both depict rocky, barren landscapes.

Thy Flesh Consumed takes place on Earth immediately after the Marine's return from Hell, possibly on a demonic modified UAC base, as evidenced by its endgame text and the episode's resemblance to Inferno's ending sequence. Until the episode was released, the first level to take place on Earth was MAP01: Entryway (Doom II).

Doom II
Doom II's Hell levels began only after the Marine enters the maingateway on MAP20: Gotcha! (Doom II). These levels are often closer to subverted human buildings, which implies that some parts of Earth may have being demonically transformed, just like some parts of the Deimos base, with the exception of the last three levels, where it seems to be entirely in Hell. The sky in these levels, where there is any, contributes heavily to the Hellish atmosphere. According to the storyline, Hell is left in ruins after the death of the Icon of Sin.

Final Doom
Final Doom's portrayal of Hell does not deviate much from previous depictions, and seems to be a combination of the original Doom's cavernous areas and Doom II's building-strewn stages. Hell levels have two different skylines; a "nightmare" red sky in TNT Evilution and crimson sky that looks like stretched, bloody muscle in The Plutonia Experiment. The Hell in TNT has a subterranean feel, and many levels take place in underground caverns. However, some levels have a techbase style, such as MAP22: Habitat.

Doom 64
Doom 64's Hell levels take a dark, cavernous, and frightening approach. There are two separate types of Hell environments: rocky, volcanic areas with a burning red sky and mountains, or similarly-themed mountainous areas with dark blue storm clouds, complete with thunder and lightning. The architecture found in most of the levels resembles castles, cathedrals or temples, replete with vicious Satanic and horrific symbolism, including plentiful pentagrams, inverted crosses, and blasphemous altars. Various human remains are strewn about these levels, including impaled heads, butchered carcasses on meat hooks, and splattered corpses on the ground. Later levels possess a skyline of burning red or green fire against a dead, black sky.

Doom 3
In Doom 3, the Marine ventures into Hell to obtain the Soul Cube. Hell is largely a claustrophobic and cavernous plane with crimson blood sky, which also resembles outer space to some extent. Both dark and fiery, although "outdoor" sections do appear. Mostly, Hell takes place in a large castle-like area, finished with huge stone bricks, broken cell gates, glowing Satanic glyphs and pentagrams, and huge oceans of magma. The conventional rules of physics are frequently violated meaning they are different.

Unlike in the Classic Doom, the atmosphere in this Hell is almost constantly noisy, typically with the crying and moaning of damned souls and extreme sizzling and bubbling of hot magma. People who enter Hell tend to experience a surge of physical energy much like that of an Adrenaline rush: seemingly able to continually exert themselves without tiring. Dubbed as the Hercules Complex by researchers, this effect is noted in the game by the player having an infinite stamina gauge - with flames shooting through it - while in Hell. This Hercules Complex also happens when facing the Cyberdemon in the Hell Hole.

Resurrection of Evil
In Resurrection of Evil, the combat engineer Marine takes a journey to Hell after activate the Phobos Labs portal pad, which leads him to the old Delta Complex from Doom 3. As the Delta Labs and other Mars City's sectors seems on dominated by a demonic vortex from the main gateway, the Marine gains accesss to Hell to return the Artifact in order to stop the invasion.

The environment of Hell has changed since the events of Doom 3, such as the place were the Marine battle against the Maledict, which is eroded and flooded by sizzling magma, and actually ressembles the first place which Doom 3's Marine gets teleported into. Unlike the previous version of Hell, which presents itself as a mix of a brimstone tomb-complex and cavernous cave-labyrinth, Hell on Resurrection of Evil seems to be divided into a few more sections, such as the island filled with demons and the whole area seems being designed on a larger scale.

Somehow, like in Doom II and Final Doom, when the combat engineer Marine enters Hell, he manages to keep his inventory with all of his weapons upon entering. H owever h is fate is unknown since the human teleportation device no longer exists on Mars, which makes the Marine unable to get back to Mars. This indicates the Marine may have died in the last battle.

Doom 3 Novels
In the Doom 3 novels, Hell is maintained and the story is largely congruent to that of the game - making it one of the few spin-offs to maintain this plot dynamic.

The atmosphere of this Hell is very similar to the game, with claustrophobic sections and cavernous planes. But there are more damned souls and possessed human bodies than in the game. The place where the Soul Cube is guarded is changed to an enormous throne which possibly belonged to the Cyberdemon. The Guardian of Hell is also absent, replaced by an enormous horde of demons. John Kane's escape from Hell is also longer and more difficult than it is in the game.

Doom without Hell
One of the primary criticisms of the classic Doom novels is that Hell was cut out and the demons instead are genetically engineered aliens. A similar criticism was aimed at the Doom movie, where the monsters were humans mutated by a Martian gene splicing experiment, rather than actual demons, and universally lacked the projectile attacks of their game counterparts.

Trivia

 * The Chex Quest analogy to Hell is the Flemoid dimension.