DOOM 2016 Fifth secret room
When you will be below the top of the tower Argent, get the door lying next to the armor. It is necessary to activate the lift.
From the control point will be visible ray, you need to work around it.
You will see a platform, on which the green light.
Climb up on it and go to the top until you see the front of the ledge.
It barely distinguishable lever that opens the door to the secret room.
Climb down on the same lift, a door to the cavity, which calls in the platform.