Doom II: Hell on Earth/MAP30: Icon of Sin



This is the final level, and it will be a tough one. Collect all items in the room, and proceed through the teleporter.

After going through, you'll alert the large demon head and it's revenant protector. This boss will shoot out projectiles that will spawn new monsters, thus time is of the essence when dealing with this boss.

Tun to the left, and use the wall with the picture of a demon head - this lowers the floor similar to a lift, allowing you to proceed. On this second step, you can use the plasma gun to take out the revenant at long range. Head to the other side, and use the demon-head wall to lower the upper step. On the south wall, you should see a small alcove with a switch. Flip it to raise a platform in front of the boss.

Head to the slime pit, and use the fully raised platform to lower it. Switch to the rocket, and attack the boss as it goes up. A good reference would be the demon head's chin, it should align to the top of the rocket launcher (when you have the status bar at the bottom.) It will take about 4-5 rockets to destroy.

The final boss is only affected by a direct hit from the rocket launcher, from a small angle. If you fire when off to the side, you risk missing the attack. It is not affected by bullets, and through a technicality of the map, is immune to even a direct hit from a BFG.

Boss spawn targets
The boss fires it's projectile once every 4.2 seconds (or twice as long on easy), in a repeatable pattern. The spawn locations are:
 * Three on upper floor, left to right
 * Four on middle floor, right first, then left to right
 * Three on lower floor, left, right then middle
 * Three in slime pit, left, right, then middle.

The shot will land at the given target, telefragging whatever is there. The monster may either be an Imp, a Demon, a Spectre, a Pain elemental, a Cacodemon, an Archvile, a revenant, an Arachnorton, a Mancubus, a Hell Knight or Baron of Hell.

Recovery items
There is a megahealth and beserk pack on the platform in front of the brain, and three supercharges on the steps: one on the lower left, one on the middle right, and the third near the alcove. If you are playing on the easy difficulties, you get access to four invulnerability pickups.

If you don't like the slime, try grabbing the radiation suits in front of the head.

Deathmatch
Players will occasionally appear with full weapons and armor. Watch out in this case.

The following changes apply:
 * The starting area has three megahealths instead of one. A greedy player may take all three.
 * The far platform has two additional backpacks.
 * The shotgun is on the lower step to the left.
 * The chaingun is on the lower step to the right.
 * The plasma gun is on the middle step.
 * The rocket launcher is on the upper step to the left.
 * The super shotgun is on the upper step to the right.

Trivia
The initial announcement is a voice recording that is distorted and reversed. When corrected, it says "To win the game, you must kill me, John Romero". If you use the noclip cheat and enter the brain, you will see the head of John Romero. This is the only instance where you can kill the boss using "normal" weapons.

The music also plays the same forwards and backwards.

You may see a mysterious wall to the bottom-right if you use a cheat. This is a map glitch, the wall has no purpose.