- For the fan-made pen & paper RPG based on Doom, see Doom, The Next Chapter.
The Doom RPG is a game designed for Java cellphones, and its story is set in the Doom universe. The game was developed by Fountainhead Entertainment and id Software and published by JAMDAT Mobile Inc. EA Mobile went on distributing the game after the company had acquired JAMDAT. The game was released at the same time as the Doom movie in October 2005, and in the UK in November 2005. In 2007, all five developers of Fountainhead became id Mobile. 
The game retains many of the elements of the original Doom games, and is likewise played from a first-person perspective. However, the game is fundamentally different in that it is a turn-based RPG. All combat and movement is turn-based, allowing the player time to select their responses in combat. The player turns at 90 degree angles and moves space by space. Although visually similar to the original games, there is a greater emphasis on the plot. It is very important to speak to the scientists and access computer terminals to obtain vital information in order to progress into the game, somewhat like in Doom 3.
Many features of the original are retained, including the status bar face, sound effects and the majority of the weapons and monsters. Notably absent are the chainsaw, Arachnotrons, and the Spider Mastermind. A difference from the original is that each monster type includes three similar monsters of varying difficulty, which are each coloured to indicate this. For example, in addition to regular Cacodemons, the player will have to fight recoloured Cacodemons called "Malwraths" and "the Wretched".
The game also adds several new features. New weapons include the axe and fire extinguisher which are useful in combat against certain enemies. The dogs from Wolfenstein 3D appear as a new enemy, known as Hellhounds. A dog collar allows the hell hounds to be captured and used as a shield or a weapon.
At least three versions of Doom RPG are currently known to exist, the older v1.0.20, v1.0.92, v1.11.61 and last 1.12.98. Version 1.11.61 has in particular the following improvements:
- Higher resolution textures
- Enhanced sound effects - v1.0.20 only had a single sound effect for item pickup, v1.11.61 has multiple sound effects (such as when firing different weapons)
- A view that takes up the entire width of the screen, rather than being contained within a small window.
- Improved particle effects
During 2007, v1.6.84 was released. This version might only be available for S60v3 Nokia phones.
The release versions correspond with releases for different performance levels of cell phone technology.
The story is a variation on the Doom 3 story. The player is a marine employed by the UAC, sent to assist members of the UAC facility on Mars, who are under attack from the denizens of hell. However, although there are similarities in the overall plot, the minor details are significantly different.
The player must visit seven "sectors" of the base that have been infested with monsters. Various scientists are encountered along the way, including Dr. Jensen and Dr. Guerard. Examining computer screens and talking with scientists, there are many rumors of a UAC scientist named "Kronos" who was working on teleportation experiments and fired by the UAC for "security breaches". As the game advances it becomes clear that Kronos is still in the base and the cause of the attack.
Dr. Guerard begins giving the player instructions. In sector 3, Mr. Nadira lures the player into a trap. The other scientists begin to express their distrust of Guerard and in Sector 6, it is revealed that Nadira and Guerard are working together. Guerard double-crosses Nadira, allowing a demon to kill him.
A second attack leaves the base in ruins; however, Dr. Kelvin opens the door to the Reactor area. The player confronts Guerard at the entrance to the reactor, who reveals that he is Kronos and transforms into a demon. After defeating Kronos, the player destroys the power couplings to the reactor, closing a portal to hell (the player is hindered by monsters that come through the portal). After having closed the portal, it is revealed that the Cyberdemon, a combination of demon flesh and human technology created by Kronos, came through the portal at the last second. The player must defeat the Cyberdemon to complete the game.
The following weapons appear in the game:
- Fire extinguisher
- Super shotgun
- Plasma gun
- Rocket launcher
- Dog collar used to capture any type of hellhound
The effectiveness of each weapon varies depending on the type of monster.
Similar to other role-playing games, the Doom RPG monsters are divided into several classes, each categorised in order of ascending difficulty.
|Monster class||Low rank||Medium rank||High rank||Base|
|Zombie||Zombie Private||Zombie Lieutenant||Zombie Captain||Zombieman|
|Hellhound||Hellhound||Cerberus||Demon Wolf||German Shepherd Dog (from Wolfenstein 3D)|
|Commando||Troop||Commando||Assassin||Heavy weapon dude|
|Lost Soul||Phantom||Lost Soul||Nightmare||Lost Soul|
|Pain Elemental||Beholder||Rahovart||Pain Elemental||Pain Elemental|
|Baron||Ogre||Hell Knight||Baron||Hell knight and Baron of hell|
Doom RPG has the following levels:
- Sector 1
- Sector 2
- Sector 3
- Sector 4
- Sector 5
- Sector 6
- Sector 7
- Des. Junction
- Items (developer map)
 Geek culture references
- Main article: Geek culture references in Doom RPG
- This article incorporates text from the open-content Wikipedia online encyclopedia article Doom RPG.
- Doom RPG FAQ by Tony8669