This level occupies the map slot MAP06. For other maps which occupy this slot, see Category:MAP06.
Go west from the map start. In front of the bars blocking the access to the red key, go to the south. In the western part of this area is a platform with a blur sphere on it. To get it, descend the stairway in the south to enter another area. Exit it by ascending the northwestern curved stairs. In the hall upstairs, look to the north. You see two sets of shotgun shells and a candle on the eastern wall. Open the wall east of the candle to find a passage to a lift that you lower and ride up to the aforementioned platform (sector 255).
Strictly go south from the red door. You see an apparently inaccessible alcove with a soul sphere in it in the southern wall. Open the southern wall in the southwestern corner to find a passage that leads to this alcove (sector 327).
Picking up the only super shotgun in the (northernmost part of the) map blocks the exit out of this area and opens four alcoves, releasing some monsters (eight imps on easy, four hell knights on medium an hard skill levels). While using the switch in the northeastern alcove lets you exit this area, pushing the northern part of the western wall in the northwestern alcove reveals a narrow hallway. Follow it to access the upper patio (sector 88) where you find a blue armor.