Ahh, the good ol' Delta Labs have come back for another visit...

You will start off right away in a teleporter, then come out, to see one of those fire zombies. Kill that, and a Revenant and some Forgottens will be on their way. Once you kill the revenant, a Hell-Knight will spawn, but, you will find the good ol' trusty BFG by you. You better conserve your BFG cells, believe me, there will be a lot tougher moments than this one later on, so bring out the double-barrel shotgun and take him down with that. Once they are all dead, take a left and around the corner to the other side, making your way to the door. You will end up in a decontamination chamber, it will malfunction, so just pass on through.

A revenant and some zombies will be working their way around the corner to your right ahead. So be ready. Around that corner, there is a 2 panel door to your right, kill the fire zombie that will attack you from the left, and then pass through the door. Two zombies will immediately attack you once you open it, pass through the door ahead of you. Now, you will come to an area you may recognize easily from doom 3 in Delta Labs, but don�t take time to reminisce, there is a Hell-Knight! Kill him, and then there will be a couple of Forgottens and a Revenant that will spawn after he dies. Once the area is clear, go left and into the teleport, with yellow lines coming out of it, you will now have teleported to a new area.

Immediately a fire zombie will attack you, once he is dead, a Revenant and some Vulgars will spawn, go to the right or left, you will end up in the same place either way, and head through the double-paneled door, through the small hallway and into the next room. Once you enter, multiple zombies will attack you from the left, and a fire zombie from the right. Once they are gone, a Revenant will spawn. Take a left and you will end up on a balcony-like area, take a left down the hall, and multiple Trites will attack you, then behind you, a Revenant will spawn. Kill them, and continue down the hall, and find another teleport, watch out for the multiple Forgottens coming your way, so jump into the teleport.

Now your environment has changed again, head forward and take aright down the hall, now a Hell-Knight will spawn right behind you, activate your artifact, and kill him with a punch, along with that zombie they pointlessly spawned near him. Then continue down the hall, and to a medium-sized area with a 2 story high ceiling. Head up the small set of stairs, and activate your artifact for the Hell-Knight that is soon to spawn. Kill him, and take a left, on top of a counter, you will find a PDA, download it, and take a right down a hallway, once you are at the end, go through the door to your right.

Now you will find yourself in a medical room, kill the fire zombie in your way, and head to the left side of the room, go to the left to get to some lockers, be warned, 2 Vulgars will spawn when you get to this point. On both the lockers, enter the code '634' and you will receive some goodies. Then turn around and down the hall, take a left on the hall, and you will end up in another room. Right away you take a look at this room and know you are screwed, but no matter, you have the trusty artifact! Explore the room, killing enemies ranging from Trites, to Vulgars, to a Hell-Knight. Then go through the door at the opposite end of the room. It will contain many water tanks used for containing organisms, kill the Trites in the room, and head through the door at the opposite end.

You will come to a hallway in the form of a 'T'. You will be immediately attacked by 2 zombies, and then turn around, collect the ammo near you, and head to the lift at your right. Once you are up, take a left and another left, through a door. You will now find yourself in the room that appears to be the room they did composition testing on the soul cube in doom 3, kill the various zombies, and head through the door behind the machine. Now you will be on the second level of the room you were in before, kill the Vulgar ahead of you, and continue on your way through the door. In this room, look out for the 2 Revenants to spawn, take a left and through the door, where a teleport is located, WEEE! teleport!

Now you will be in a room that appears to be a large teleport, which it is, go through it, and teleport to HELL!.