The Shaft/Interior D unusual. There's a ceiling that opens and closes, walls sliding, mines, and Lasers. Take the lift to the upper area of the room, but watch out for the pesky mines. Halfway up the room you'll see a section of wall that's opening and closing. That's where you want to go. There's some Tempest ammo on the opposite end of the room if you wanna grab it before zipping through the closing section of wall. Head through the door, which leads to Shaft/Interior A.