MAP10: Onslaught (The Plutonia Experiment)

MAP10: Onslaught is the tenth map of The Plutonia Experiment. It uses the music track "Demons On The Prey" from Doom. In the PlayStation version of Final Doom it is the final level.

Walkthrough
Turn 180 degrees fast and kill the chaingunner before he kills you. At the same area there is the blue key surrounded with rails and stone pillars, go and take it but watch your moves, every pillar you go through the door next to it will open revealing monsters. After taking it go and open the door next to the blue skull floors, behind there is a switch, clicking it will lower these blue skull floors.

Run to the left to the circular area with surrounded wooden doors, however these doors will reveal an onslaught of chaingunners! Open the brown door (behind is a Baron of hell). Take note that the chaingunners will be constantly revived by hidden archviles, so don't stay here too long. Click the switch behind and you will instantly be lowered down to the sewers. Go right and to the second left area there is a switch, clicking it is necessary, head back and go forward and up the stairs. Go up on another stairs, on the right click this switch and get back to the main area from this way.

The yellow key is now accessible, take it and get ready for another spawning onslaught. After dealing with this, go to the yellow keyed door and open it, two lefts on the way the red key is there, take it and go back again to the area where you took the yellow key, there you will find a switch that needs the red key, click it and click the switch behind it.

The exit is nearby now, head back again to the area behind the yellow keyed door and you'll notice the red door is opened. Behind it go and run ignoring everything (or not) in your way to the exit.

Secrets

 * 1) A ways into the level you will make it to a grey brick sewer-like area. In the tunnel to the right are two paths branching off to the left and right; go into the right one and open the misaligned wall to the left to get some goodies.
 * 2) After passing through the sewer area, you'll arrive at a beige-walled computer room. There is a combat armor resting atop a CPU block in the corner of the room. To lower it, walk up the stairs leading outside. When you reach the top, the wooden board gating the way will lower, but rather than passing over it, return back down to the computer room and quickly grab the lowered armor.
 * 3) After making it back outside once you've passed through the sewer area, there will be a sunken stairway leading down then back up to an earlier part of the level. At the lowest point of the staircase, press the use key against the left (west) wall to lower the ground on both sides of the staircase. The far end of the right (east) side (opposite the wall you pressed to lower the floor) has a hidden alcove in it.

Routes and tricks
You can cut out the sewer area and the yellow skull key entirely by accessing the red skull key via the window rather than the traditional route.

The yellow skull key door has two "posts" indicating that it requires the yellow key immediately outside. Use the steps to get on top of the post nearest the window; then strafe-run through the window to get to the red skull key.

This trick was used by (at least) Juho "ocelot" Ruohonen in the record below.

Trivia
In Playstation version of Final Doom, this is the final map with final boss Cyberdemon in area with Chaingunners.

Records
The Compet-N records for the map are: