MAP23: No Way Out (Memento Mori II)

MAP23: No Way Out is the twenty-third level of Memento Mori II. It was designed by Eric Sargent and uses the music track "Mirage" by Mark Klem. It contains a separate area for multiplayer competition.

Mission briefing
According to both the text file and the Infopack:


 * The demons have sealed the emergency evacuation route and we can't get out. We've sent several scouts in an attempt to find another exit, but all attempts have failed.  We did manage to get an image of the complex from one of the scouts before we lost contact with him.  Send someone to move through the complex and find an alternate route.  Please hurry...  the demons are closing in on the area we have barricaded ourselves in.

Walkthrough

 * Letters in italics refer to marked spots on the map. Sector numbers in boldface are secrets which count toward the end-of-level tally.

Secrets

 * 1) After obtaining the red keycard, enter the red key door east of the teleporter you arrived at and flip the switch in the northeastern compartment. Enter the northern computer room to find that one of the computers (sector 52) has lowered to reveal a green armor. Grab it and an alcove will lower to the south to reveal three (one on easy skills) imps. Kill them and enter the corridor within the alcove to find another imp and a chaingun.
 * 2) In the yellow keycard room, there is a switch in the western hallway. Flip it and the walls beside the stairway will lower to reveal two compartments (sector 294); the western one contains a chaingunner, two armor bonuses and a box of bullets; the eastern one contains a chaingunner too, a stimpack and a box of shotgun shells. Both compartments count as one secret.
 * 3) Once you obtain the yellow keycard, reenter the last room with a yellow key door to find that the northeastern compartment has opened in the back to reveal a backpack (sector 149).
 * 4) In the room beyond the aforementioned yellow key door, flip the switch to raise a bridge to an alcove with a box of rockets and a rocket launcher. Enter this alcove, exit the room and look to the southwest to find that a compartment (sector 147) has opened to reveal two health bonuses and a switch.
 * 5) After going through the yellow side of the starting teleporter, go through the yellow key door and flip the switch at the end of the hallway. Enter the circular room, lower the walkway (by stepping onto the platform with the blue armor) and look to the north or south to find that compartments (sector 178) have opened at either side. The northern one contains a box of shells, a bulk cell and a computer map, while the southern one contains two armor bonuses, a stimpack and a plasma gun. Both compartments count as one secret.
 * 6) East of the aforementioned circular room, a section of the southern wall (sector 206) has blinking lights in front of it. Open it to find two health bonuses, an armor bonus, a medikit and a switch.
 * 7) Flip the switch in secret #6 to lower the bottom of the northern window (sector 196), allowing access to the outside. Encountering three sergeants, (a chaingunner on medium and hard skills,) two troopers, five (four on easy) imps and a demon, you will find two health bonuses, a stimpack and a berserk pack, as well as a hole in the southern wall with a teleporter behind it.
 * 8) Flip the switch in secret #4 and head to the hole in secret #7 to find that it has opened, allowing access to the teleporter as well as a box of bullets, a box of shells, a box of rockets and a bulk cell (sector 201).
 * 9) Enter the teleporter in secret #8 to find (an imp on medium and hard, ) two chaingunners and a set of four teleporters in front of you. The southernmost one has a green torch in front of it; enter this one to encounter (two imps on medium and hard skills and) a hell knight; enter the third teleporter from the north in this set (clue: counting from the side where you entered the room it's the second one, and there are two candles in each corner). You will find yourself in front of a switch; turn around to see another switch and flip it (opens four switches). Trigger the other switch to lower yourself into the room with (skill dependent) two/six/seven imps and then press the northernmost switch. Enter the teleporter revealed as a result (clue: different pentagram on this one) and you will be taken to a secret room (sector 231) with two troopers, two sergeants and a BFG9000 in the center.
 * 10) Head to the northeast of secret #9 and press on the metal walls to lower a corridor (sector 242) containing five health bonuses.
 * 11) Head to the southeast of secret #9 and press on the metal walls to lower a corridor (sector 243) containing five armor bonuses.
 * 12) Head to the southwest of secret #9 and press on the metal walls to lower a corridor (sector 244) containing five health bonuses.
 * 13) Head to the northwest of secret #9 and press on the metal walls to lower a corridor (sector 245) containing five armor bonuses.
 * 14) Grab the BFG 9000 in secret #9 to open alcoves containing monsters: (four hell knights on medium and hard skills,) (six chaingunners on hard,) four (two on easy) revenants and a baron of hell. In the eastern compartments where the two pain elementals came from, one section of wall (sector 238) has a white light instead of a yellow light. Open either one to find a megasphere.
 * 15) From secret #14 return to the window mentioned in secret #7 and proceed southwards through the hallway. West of the entry to the passage surrounding the blue keycard room, there is a section of the northern wall (sector 260) bordered by metal, with panels taller than the others. Open it to find a hidden room with an imp, two sets of shells and an invulnerability. Press the switch in this room to lower the invulnerability for acquisition.
 * 16) After revealing and using the second (eastern) teleporter beyond the blue door after the blue side of the starting teleporter, you are at the north of the map. After passing through the first door, press either switch to the west to access the computer room. After this, look to the east to find that two of the computer panels are identical. Press on the central one to find a light amplification visor (sector 380).
 * 17) Leave the computer room to the east and descend either stairway. At the river at the very north of the level, there is a switch on the southern wall. Flip it, head to the northwest of the level, and climb up the metal stairway. Normally, at the apex of this staircase is a pedestal with a stimpack on it; if the switch was flipped, this will be lowered. Enter the now accessible hallway and open the door to find a soul sphere (sector 355).
 * 18) Grab the soul sphere in secret #17 and an alcove (sector 371) will open in the north to reveal (a baron of hell on medium and hard,) two hell knights and two imps, also containing a box of bullets and a box of rockets. This alcove counts as a secret.

Bugs
Thus, the following items are unreachable: A chainsaw, two shotguns, three super shotguns, a chaingun, a rocket launcher, two plasma guns, two BFG9000s, three bullet boxes, three shell boxes, three rocket boxes, three bulk cells, two medikits, six health bonuses, a soul sphere, a megasphere, six armor bonuses, and both partial invisibilities.
 * Because of the presence of items not flagged as multiplayer-only in the deathmatch arena, you can only get 83% items on Ultra-Violence or higher and 84% on Hurt Me Plenty or lower.

Routes and tricks
From the starting point, after entering the teleporter from its south side, i.e. moving straight, it is possible to make a glide through one of two 32 unit wide gaps to the left (west), directly to the exit room. If successful, the trick cuts out the entire level and allows finishing it below 5 seconds.

Current records
The Compet-n records for the map are:

Trivia
This level has the highest total number of monsters of all Memento Mori II levels: 224 on Hey, To Too Rough or lower, 321 on Hurt Me Plenty and 374 on Ultra-Violence or higher.