In the room with the switch opening the way to the red skull key, open the faded brick wall in the southwest to find four sets of shells, four clips, three rockets, four cells, and four stimpacks. (sector 460)
At the north of the plasma rifle building, walk onto the first step to the west. Immediately run to the east of the building and drop into the newly-revealed hole to enter the former humans' corridor, containing a berserk pack. (sector 458)
In the room with the combat armor southeast of the plasma rifle building, open the center portion of the eastern wall to find a stairway leading to the Lost Souls' cage south of the rocket launcher building, containing a soul sphere. (sector 427)
At the southwest side of the building east of the red key, there is a section of wall (linedef 297) with linedef type 127 (build stairs by 16 map units, fast, switch-activated once) tagged to the nearby, yet to be built staircase, even though it has no switch texture, and a switch with an identical type and tag is found at the very east of the map. This may likely have been a debug switch, meant to test if the stairs would build as intended, that the author forgot to remove before the megawad's release.