You will reach a room ( sector 94) containing a rocket launcher and other supplies. This leads to a room with a nukage "river". From the rectangular room past the starting area, leave through the southern corridor.Open it to reveal a small room containing a backpack, a medikit and a box of shells. In the short corridor where you start the level, part of the south wall is misaligned.This room contains a box of rockets, but as you walk around the perimeter, you may trigger a trap where the central structure lowers to reveal several monsters, as well as a medikit and a second box of rockets. To the east of the exit staircase is a dark room with a blue flashing light. You can get on to the ledge using the brown lift at the east end of the room - be careful, as when you step onto the ledge the wall behind you will open and release a number of monsters. If you leave the rectangular room after the starting area through the north corridor, you will come to a room with a wide ledge holding a megaarmor pickup. Throwing the switch has raised a bridge to the exit door in the next room - climb the staircase, cross the bridge, go through the exit door and throw the switch behind it to finish the level. Go north up the staircase and throw the switch at the top, then go through the yellow door to the right. You will enter a brighter room containing the yellow keycard, so pick it up by the window. At the bottom of the staircase, go due north and turn right at the end of the corridor, then turn left and left again. Go south and open the blue door, behind which is a maze area. Leave the blue key area through the west exit and go south at the junction to a room with a raised metal ledge. If the doors close before you leave the room, throw the switch on the north-east wall to open them again.
The doors to the structure open automatically when you approach them - go inside and take the blue keycard. Shoot or squeeze through them, then go west up a staircase to a round room with a central structure. Go down the south corridor and follow it to a room with several barrels. Go through the door to a rectangular room with two corridors leaving it to the west. You begin in a short corridor, facing a door. Sector numbers in boldface are secrets which count toward the end-of-level tally. Letters in italics refer to marked spots on the map.