

If you pick it up, be careful of an ambush from five different sides of the room.

In the C-shaped hallway on the west side of the map, there is a door in the middle of the hall that leads to a chaingun. Press the switch on the right path to raise some blocks in the pit so you can access the exit. Take the left path first and press the switch here, this will open up several monster closets as well as the switch on the right path. Go through them into the next area with a nukage pit dead ahead along with the exit door, and two paths branching off to the sides. Head for the northeastern part of this area near the blue bars to find the blue keycard, and then press the blue switch next to the bars to open them. Open it to find a large cargo room with a nukage canal running through it. Ignore it and take the other path in the canal until you reach a red door.

This door leads back to the starting point. Go all the way through this canal till you see a door. Go south, into the C-shaped hallway, and go all the way through it and open the next door here to find a canal. Flip the switch and head back into the large hallway, then go west all the way until you reach the red keycard. Head down the field here and through the rocks to a switch that has a red bar next to it. Open the door to the north instead of taking the hallway to wind up in an outside area. Take the door to your right, and follow it all the way to the next door into a large hallway. There are two doors to take, one in front of you and one to your right. Sector, thing, and linedef numbers in boldface are secrets which count toward the end-of-level tally. Letters in italics refer to marked spots on the map.
