Quake 2 Easter Egg - Doom Poster

1. This egg-of-sorts is in a hard-to-find secret area in the Upper Palace in the City unit.
2. Find your way to what looks like a mine shaft that leads to a room made of gold-colored rocks and yellow lights.
3. There should be a pool of moving green slime and an environment suit nearby.
4. Along the edge of the pool, near the right, is a button by the floor.
5. Just wander around the pool (look down) and eventually you will run into it.
6. Use the environment suit, enter the pool and follow the passage to a Secret Area.
7. One of your fellow marines has made a secret hideout here, featuring artifacts such as a picture of a sports car and a Doom poster.