Doom/Storyline

The story starts out with you, a space marine(aka "Doomguy","Flynn Taggart" or "John 'Reaper' Grimm"), are forced to work with the UAC for assaulting a superior officer (the officer ordered him to fire at citizens). The UAC was experimenting with teleportation when something went horribly wrong! The teleporters have literally opened the gates to Hell! You are sent in as part of a response team, but your comrades are slaughtered right in front of you. Yet, whether it was a sign from God or just plain luck, you were left alive. Realizing you are the only one left in the entire base, you must prevent the demons from getting to earth. You pick up your handgun, and the race for humanity's survival is on!

You've done it! The Spider Mastermind that started the invasion is dead. You set down your BFG 9000, knowing you will have no further use for it... or at least you hope....