This is the last strictly "proper" level of the first episode, and it's pretty long and difficult. Start by opening the door and blasting the two barrels to either side to kill the two shotgun marines who will ambush you from the sides and the Spectre that runs towards you. Sit here for a while and kill off the various Imps and marines as they approach until it looks like the coast is clear. You can have a look around this area to finish off any stray enemies and pick up some goodies, but the only way you can leave for the mean time is to the left of the area (looking from the way you start the level facing, otherwise right on the map). Head that way and you'll find a room with a fading light. Kill the Imp on the lift in here, and go up it. Kill the shotgun marines and Imps at the top and work your way around to a room with two shotgun marines and the yellow keycard in it.
Drop down to the floor. Around the corner from here (near the window looking outside) you'll see a yellow keycard door. Head inside and work your way around the centre section killing off the enemies. Once they're dead, use the lift on one side to go up to the centre section. Clear it out and you can go to the end for a rocket launcher and a box of shotgun shells. Go back down and find the corridor with the illuminated entrance. Head all the way down here, past the blue keycard door, to the stairwell going to the right. Up here, kill the marines and Imps, then approach the pillar and kill the shotgun marines as the pillar drops. Ignore the pillar for now and kill the enemies in the vicinity - some marines come from the open passage to the right, and some Imps come from behind the automatically-opening door. Once they're dead, snipe some of the various enemies on walkways from the edge of the path you're on. Now, run to the edge of the stairs you came up to trigger the pillar to lower again, then get on it and ride it up. Once it's high enough, sprint over the edge and you'll get over the barrier at the edge of the walkway and land in the slime pit. Now, sprint over to the Radiation Suit you can see (providing you went off the right edge of the walkway - if you didn't, you can go left to find another secret platform with some medikits and ammo, and the automatically-opening secret door at the end will lead to a lift back up to the staircase and a Backpack). When you get the Radiation Suit, face the wall opposite it and use the switch to open the wall. Go up the stairs for a box of rockets, then throw the switch and turn around. Head down the stairs to the slime again. Go out the other side of this tunnel area, where there's a dead-end walkway you saw earlier from one of the windows. Head around it, and you'll see a long slime path to a small platform with a Soulsphere on it. Grab it to trigger the wall to open, and you'll emerge out near the start of the level.
Make your way back to the pillar. You can ride it again to get the other secret if you haven't already. Head down the right-hand path, all the way to the end (kill the enemies along the way. Up the lift, follow the fading-light room to the end where you'll find the red keycard. Turn around and head back to the fork in the pillar room, watching out for the secret wall section that opened releasing some marines and Demons. The automatically-opening door on the left side of the fork leads to a fading light area up a lift which contains a box of rockets and a Chainsaw if you don't have one already. Either way, head back to the start of the level, and find the red keycard door. Go out on to the walkway and grab the blue keycard (kill the enemies here too, if you haven't already).
Be careful, as now numerous secret areas have opened up in the walls about the place, unleashing more enemies about. Make your way to the illuminated corridor leading to the pillar room, where you'll find the blue keycard door. Head through, killing the enemies as you go. When you reach the fork, head right, as you can't open the door to the left. Follow the path around, killing the various marines and Imps, and hit the switch at the end to open the door. Retrace your steps, kill the new enemies that have appeared, and sprint across to the exit door. Kill the sneakily-placed shotgun marines and Imp, and hit the switch to leave the level.
Secrets[edit]
- In the bridge area at the south of the map, there is a pillar-lift that lowers enemies. Stand on the pillar, and as it rises, jump to the southern area. There's a chaingun, backpack, ammo and a medikit.
- In the bridge are, jump into the northern slime area. Get the radiation suit, and look for a nearby switch that will open the door to a set of stairs. There's some health inside.
- North of the previous secret is a supercharge.
- The last secret is available once you get the blue card key. Look for a newly opened area just north of the blue key gate, and use the right wall. Only the inside corridor counts as a secret, but you can go outside for partial invisibility.
Deathmatch[edit]
- A mega armor is located at the fourth secret, in the bottom-right corner of the map, as well as a few additional medikits.