Map 21: Nirvana

Start on a silver platform with 20 Medikits, 16 Health Bonuses, and a Super Shotgun. Kill the Imps directly ahead. Take the north-western teleporter closest to where the Imps were.

You'll arrive in a circular structure. Defeat Spectres and Shotgun Guys. Near the southern teleporter, a monster closet opens, revealing four Revenants. Use the BFG9000, followed by the Plasma Gun if needed.

Enter the Revenants' closet to find Shotgun Shells and a switch. Flip the switch to lower the inner wall around the first teleporter you used.

Take the other teleporter to a brown room. Flip all four switches on the metallic triangular panel.

Examine the bottom of the raised platform steps to lower it. Ride it up, then jump to the panel to grab the Rocket Launcher.

Climb the raised steps and kill Imps and Mancubi down the eastern stairs. Be aware of enemies teleporting back to the starting room.

Head down the eastern stairs. Hitting the green switch on the northern wall opens a hidden door back to the starting room for extra health.

Take the southern teleporter in the eastern section. Be ready to fight Imps in the enclosed room. If you have the BFG9000, use it.

Examine walls to reveal a room surrounded by Imps, Pain Elementals, and other enemies. Use the BFG9000 to clear most enemies, then finish with other heavy weapons.

Collect the Backpack from the south-east corner and another in the north-west corner.

To get the Megasphere in the north-east corner, teleport back to the previous room. Hit the green switch on the southern wall, then quickly teleport back to grab the Megasphere before the platform retracts.

Return to the starting room and take the remaining teleporter. Raise the yellow gates.

Enter the large room with enemies on stone columns in a slime pool. Grab Radiation Shielding Suits from the slime.

Prioritize killing Mancubi and Hell Knights, then Imps on the stone platforms. Examine the smaller columns to lower them. Use Radiation Suits as needed. Grab the Invulnerability artifact near the west wall if necessary.

To get the Blue Skull Key on the north-west platform, lower the platform just east of it. Shoot barrels on the platform to kill nearby Imps, then cross the gap to get the key.

Return to the south-east part of the room and lower the column near the entrance ledge to get back up.

Head to the blue gates. With the Blue Skull Key, you can now raise them.

In the eastern section, platforms hold Chaingunners and Imps. (The text cuts off here.)