DOOM

In the future, humans have left Earth and settled throughout the galaxy. On Mars, the Union Aerospace Corporation has built a radioactive waste facility and allowed the military to conduct teleportation experiments on the nearby moons Deimos and Phobos. A few hours ago, the base on Mars began receiving garbled distress calls from Phobos, while Deimos has disappeared completely. With all attempts to make contact failing, you and your team have been sent to investigate. Upon arrival, you secure the perimeter while the rest of your team enters the facility. As you stand guard, your radio crackles with the sound of gunfire, cracking bones, and bloodcurdling screams, and then falls silent. Alone, with no way to leave the planet and no means of defense other than your trusty pistol, there is only one way out—into the complex of death and the horrors that await you there. If you plan to get out of here alive, you'll have to fend off hordes of demonic goblins, ghostly spirits, and your undead former comrades, who are waiting to tear you to pieces. So grab the nearest shotgun and blast your way out of this insane chaos!

Story

The player takes on the role of a marine (unnamed to represent the player persona), "one of Earth's toughest, hardened in battle and trained for action", who was imprisoned on Mars after attacking a senior officer when he was ordered to fire on civilians. There he works for the Union Aerospace Corporation (UAC), a multiplanetary conglomerate and military corporation that conducts secret experiments on interdimensional travel. Lately, the teleportation has shown signs of anomalies and instability, but the research continues nonetheless. Suddenly something goes wrong and creatures from hell pour out of the teleportation gates on Deimos and Phobos. A defensive response by the bases' security forces fails to stop the invasion and the bases are quickly overrun by the monsters; all personnel are killed or turned into zombies A military commando from Mars travels to Phobos to investigate the incident. The player is tasked with securing the perimeter while the assault team and their heavy weapons are brought inside. Soon radio contact is lost and the player realizes that he is the only survivor. Unable to pilot the shuttle off Phobos on his own, the only way to escape is to go inside and fight his way through the moon base complexes.