Word has reached Doomguy of demonic activity near a small starport in a run-down district of the city. He hauls himself over and finds imps and zombies crawling all over it. To reach the masterminds behind the incursion, he has to push through condemned apartment blocks, a festering sewer system, an old UAC cladding factory, and a stinking rubbish dump. Time for some grime and punishment.