Map 24: The Chasm

From the starting corner, kill the Cacodemon to your left and note the Blue Door nearby.

Clear the open area, then head back and take the left path to a door. Go around the area, ignoring an inaccessible opening on your right for now.

Past the opening, shoot the Imps on an island with rockets and clean them up with a shotgun. A big health pack is on the island.

If you walk off the ledge near the island, you can find a semi-hidden Rocket Launcher.

Continue around this area to find a door leading to another ledge with rockets and health.

Nearby is a narrow ledge with a Shotgun; you will return to this soon.

Go back to the starting area and take the wide path to the door.

Prepare your super shotgun for half a dozen Imps to your left. Take them out.

Go LEFT first. Use a chainsaw to save ammo and rush the Imps in the small cubbies. Collect the small amounts of ammo (rockets) and health found here.

Search every cubby for the Blue Key Card.

Return to the door and search the other half of the room. Use your Super Shotgun to deal with a hidden Cacodemon, then switch back to your chainsaw for Imps in short paths. Gather items.

Head back to the Shotgun path. Warning: Save before proceeding.

As soon as you pick up the Shotgun, three Cacodemons appear behind you. Kill them all with your Rocket Launcher.

Jump down into the room they came from for [SECRET 1/4].

Drop into the acid. Go right and between the walls to find a teleporter to the top of the red platforms.

From the red platforms, go right to follow a path with minor ammo to another teleporter.

Enter the teleporter to find a room. Go RIGHT first, moving slowly.

As you round a corner, a Hell Knight will appear in the dark. Shoot it and make it come to you; DO NOT go to it.

After killing the Hell Knight, get your Rocket Launcher ready. Back the way you came is a MONSTER CLOSET filled with Chaingunners. Inch forward, wait for the sound, turn around, and blast them. Collect the bullets.

Continue past where the Hell Knight was to find a SWITCH.

Head back and go LEFT. This path leads to Pinkies and Specters. Use the Chainsaw or Punching, corner them, and make them come to you.

Past them, find another Switch.

Head back and take the last passage. A room of Pinkies will teleport to your hallway. Punch them one by one from a corner to save ammo. Once 2-3 are left, shoot them from the window. Gather ammo and items.

Find the third and final Switch in this area.

Go back to the teleporter and use it. You are back in the acid area.

Drop into the acid and take the teleporter to the red ledges. Take these down to the starting area.

From the starting area, head straight and to the left to find stairs leading to a room. This area is [SECRET 2/4].

As you enter this area, a MONSTER CLOSET on the right opens with many Imps. Use rockets to kill them.

To the left of the monster closet is a computer terminal. Hit it to lower a platform behind you. Ride it up for various items; this counts as [SECRET 3/4].

Head back down. From the stairs, examine the cubbies on the left. One has a Switch that releases two Hell Knights from the Radiation Suits area. Hit the switch, run back to the stairs, and use rockets on them.

Behind one of the Radiation Suits is a Megasphere.

Explore the small area. Imps are in small pathways. A back pathway leads to another Computer Terminal (with Imps and Chaingunners).

Hit the terminal. You get bullets in a room behind you, but many Chaingunners are unleashed in this area. Return to the Radiation Suit room and kill them all, using corners for safety. Explore new small rooms with ammo.

Grab the Radiation Suits and the Megasphere and go down the stairs.

Warning: Be quick. Drop into the acid and go straight to the wall, then turn left. Follow the wall around the outside of the area to an opening.