E2M9: Fortress of Mystery (Doom)

E2M9: Fortress of Mystery is the secret map in The Shores of Hell in Doom, and can be accessed from E2M5. It features some Barons, a horde of Cacodemons and not much else of interest. It uses the music track "Untitled".

Walkthrough
When the level starts you will immediately be attacked by four Barons of Hell surrounding you. Find a safe spot and take them out with your most powerful weapon. Once they've been taken care of, pick up the various weapons and other goodies in each of the "arms" of the first area. Afterwards, go through the door in the eastern "arm". The next area holds eight Cacodemons. Pick up the Soul Sphere in the center of this room if you need it. Once all the enemies have been disposed of, head to the eastern end of this "+"-shaped room. There are two lion-faced reliefs on this wall. Open the wall between them to reveal the level's exit room. Press the skull switch to the left to get the blue key, then open the blue door to get the red key. Open the red door to get the yellow key, and finally open the yellow door to reveal the exit teleporter.

A much safer option is to use the apparent dislike between Baron's and Cacodemons. If you immediately start running in circles around the Barons of Hell, you will 'Sheppard' or round them up and they will follow you as a group. Now run into the eastern arm and do the same with the Cacodemons, running a circle around them - do not fire as this gives them time to zero in on you. Then run back to the Baron room, accept a blast or three from the Barons and Cacodemons, and run into one of the corners. At this point, you can expect to be completely left alone as the Cacodemons and Barons will have hit each other and start a huge infighting sequence. You can sit back and watch, then finish one or two creatures which have been badly damaged. In using the Sphere you'll regain any health lost and more plus won't have lost much (if any) ammo. This seems to be the designers intention, as in each room, there are bodies of the other creature.

Secrets

 * 1) The exit room counts as a secret.

Records
The Compet-N records for the map are:

Trivia
Prior to entry of the level, the fortress does not appear on the intermission screen. After entering the level, the fortress fades in on the map, and remains on the map from that point on during Episode 2.