Changes

The game stars an unnamed marine, a survivor of [[Bravo Team]] from the original Doom 3. He awakens after the ambush on his squad and is soon confronted by [[Dr. Garret]], who presents him [[Sam]], a flying droid capable of opening doors and hacking computers. Together with Sam, the survivor makes his way through the [[Mars]] facility, battling zombies and demons on his way through the base. His goal is to reach a port where a spaceship full of surviving members of the [[UAC]] facility is preparing to blast off. On his way, the marine meets a few survivors, collects valuable information through Sam, and visits [[Hell]], where he closes the demon-spawning portals. Eventually, the marine is forced to leave Dr. Garret behind, and Sam sacrifices itself to support a closing door to the spaceship. In the process of the escape, the only the data which could be used to implicate the UAC in the incident is left behind.