Doom Episode 1 Secrets: Knee-Deep In The Dead (1993)

E1, M9: Military Base (Secret Level)

Here we have an action-packed map built like a maze. It contains 2 secret places.

Secret 1

This secret can be accessed in two different ways. From the central area near the start point, two of the three stairways lead to rooms that contain locked yellow key doors. In either of these rooms, one of the corners will drop down when you walk on it, revealing a secret area.

Secret 2

In the exit room, one of the walls has a different look and texture. This is a secret door leading to a room with lots of items.

The following video walkthrough of the Doom secret level illustrates both of the map’s secrets.