Duke Nukem Wiki
This page refers to the level in Duke Nukem 3D. For the Nintendo DS game, see Duke Nukem: Critical Mass.

Critical Mass is the eighth level of The Birth in Duke Nukem 3D.


There are 4 secrets in this level.

Secret 1: Homer's control room

This secret can only be visited before one of the room blows up and collapses. After going up a spiral staircase and reaching the door, explosions will begin. Open the door, but do not run towards the safe, white place behind the explosions. Instead, wait while the ceiling is collapsing at the door. When it is very close from squishing you, you should notice that one of the walls opposite to the door where you are is opening. Quickly run into the room it unveils and be careful not to get squished.

You will find yourself inside the room mentioned in the Easter Eggs section on this page. There is an atomic health hidden behind the machinery. Also there is a teleport that will get you out of the room and to the next part of the level, behind the collapsed room.

Secret 2: Bonus first aid

After you pass the room with water, some octabrains and two crushers where you need to avoid getting squished, you will be inside a small room with two first aid cupboards on the wall. One of them includes an atomic health and the other a large medkit.

There is also a monitor. Press use/open at the front of it - a small hidden room will open on your right. There will be portable medkit.

Secret 3: Messy RPG

Inside the room after blue keycard door, simply shoot the ooze cans (the metal bottles with green substance that explode upon being shot). Part of the wall will blow up, revealing a small place with RPG.

Secret 4: Fly for a Shrinker

This secret place is located in the same room as the previous one. You will however need a jetpack to reach it - unfortunately it cannot be found in this level, so you have to keep one from the previous levels. Just fly up to the ceiling then towards the wall opposite to the door - there will be a small cave with shrinker and rockets for devastator.


See Also: Written/Pictorial Walkthrough by 3D Realms


Duke Nukem 3D 100% Walkthrough- Critical Mass (E4L8) -All Secrets-

Easter eggs

  • One of the secret places in this level has a large control panel with doughnuts on it and just behind it is a sign that says "Sector 7G". This is a reference to Homer Simpson and the place he works in.


  • This level contains a second exit button near the end of the level. This exit button was intended to serve as the regular exit button during multiplayer. It can be found inside the wall at the end of the hallway just before the end of the level. The wall is located between the door with the Red Access Card Panel and the door to the office across the hall.



The authorship of this level has been disputed. Richard "Levelord" Gray partially contributed to the level, but for reasons that are unclear, he was never officially credited for his work on it. The degree to which Gray and Keith Schuler each deserves credit for the final design remains controversial. (See The Birth#Disputed authorship for more information.)
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