MAP21: Den of the Skull (Requiem)

MAP21: Den of the Skull is the twenty-first map of Requiem. It was designed by Anthony Galica, and uses the music track "The Everlasting Negative" by Mark Klem. It is the biggest level in the megawad.

Description
According to both the text file and the Requiem info pack:


 * You are trapped in the den of the skull, and it is not a very safe place...
 * only your best fighting ability and intelligence will help you through. There is a large and complex world ahead of you that you must get through, filled with surprises and wonders as you fight evil to save yourself and the world once more.. otherwise, it will be your REQUIEM they are singing... Keep in mind that the exit is for Authorized Personnel Only.

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 entering the teleporter at the beginning of the level, shoot at the southeast corner of the room to find a computer map, a backpack, and (on Hey, Not Too Rough or lower) a berserk pack. (sector 497)
 * 2) Inside the metallic room before the X-shaped teleporter, push on the set of lights at the east to find a switch. Press it to open an alcove with combat armor. (sector 532)
 * 3) After lowering the lift around the X-shaped teleporter, quickly rush to the north of the room to find a closet with two boxes of ammo, a box of shells, two boxes of rockets, two bulk cells, a backpack, and a chainsaw. (sector 537)
 * 4) At the room beyond the yellow door, a portion of the northeast wall at the winding staircase in the southeast of the room is not properly aligned. Push on it to be lowered into a passageway leading to a balcony overlooking the storage facility, containing a soul sphere. (sector 515) Note that you can only push on the wall to trigger the lift once; if you do this, and then fail to enter the passage before the lift rises again, you will be unable to enter this secret.
 * 5) At the outdoor, mountainous region, press on the northernmost wall, and it will lower, revealing a stairway leading to a light amplification visor. (sector 119)
 * 6) While inside secret #5, press on the wall behind the visor to access a cavern filled with Imps, with an invulnerability at the end. (sector 74)
 * 7) While inside the prison, look to the south to find a misaligned portion of the wall. Push it to find combat armor. (sector 254)
 * 8) After shooting the switch to raise the bridge on your way to the switch that opens the exit, jump into the same switch, and push on it to open a compartment containing a soul sphere. (sector 320)
 * 9) In the penultimate room before the exit, there is a pillar with a megasphere on it. Press on the "Tei Tenga" monitor, wait until the lift has lowered, and then push on the monitor directly to the north of it to lower the outer edge of the pillar. After this, immediately run up to the pillar to obtain the megasphere. (sector 123) The secret here cannot be reached, as it is too small and too close to the pillar for the player to completely step on.

Bugs
The level's REJECT lump is 65536 bytes too small, which will result in demos recorded on this map desynchronizing even with the same executable used to record them. It is also impossible to obtain 100% Kills on the original version; the monster teleports into the second room, intended to trigger when fighting in the sky at the west of the map, will fail, as the storage sector the monsters are in is connected to a sector with a deep water effect, which monsters cannot see into or out of. To resolve both issues, save the map into its own file ("req21.wad," for example) using a level editor, and then run ZenNode on the file using the command line arguments -rz req21.wad (or whatever you named the file,) which will, aside from rebuilding nodes, create an empty REJECT. Although rebuilding the nodes this way will create rendering errors in the sky segment and the bridge in the mountainous region, and will also create a gap in the middle of the bridge, this will allow 100% Kills.

The gargoyle switch in the 4 swiches area lowers floor of two sectors, 521 and 535, and allows the player to return to the blue key room. This switch, however, works only once. If the player chooses to return to the blue key area (or anywhere past sector 521) and then uses the red cross teleporter, he will become trapped.

Because one of the secrets cannot be triggered, only 88% Secrets can be obtained.

Routes and tricks
To fix the REJECT issues and allow demo recording, Rudy Jurjako created a fixed version of the map with rebuilt nodes, on which he recorded his 8:10 UV max demo, that can be found here. However, this only works with Rudy's demo; every other demo available for this level on Compet-N will desynchronize with his fixed version. They will only play back with the version of the map created using the method outlined in Bugs.

Although Rudy's UV max demo is technically faster, Xit Vono's 8:38 demo took its place on the table regardless, as it obtains 100% Kills, whereas Rudy's only obtains 96%.

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