DOOM + DOOM II

Get 20 kills using the berserk powerup in a single level.

Find a secret level.

Find a secret area.

Gib three or more enemies with a single rocket explosion.

Complete any monster-filled level with 100% kills, items, and secrets.

Kill all monsters in any monster-filled level on 'Hurt me plenty' or higher.

Kill 5 enemies in 5 seconds with the Plasma Rifle.

Reach the end of 'DOOM'.

Reach the end of 'DOOM II'.

Crush a corpse in a door.

Reach the end of 'TNT: Evilution'.

Get 3 multi-kills with the Shotgun.

Get 25 kills with your Fists in a single level.

Shoot 200 bullets consecutively with the Chaingun.

Finish a level with 100% items picked up.

Kill one of every enemy.

Immolate a total of 30 arachnoid enemies with the Incinerator.

Reach the end of 'Legacy of Rust'.

Reach the end of 'Master Levels for DOOM II'.

Complete a level on Nightmare difficulty.

Reach the end of 'No Rest for the Living'.

Cause an enemy to kill another enemy.

Kill only a single enemy with a BFG9000 blast.

Finish a level with 200% armor and 200% health.

Reach the end of 'The Plutonia Experiment'.

Obliterate 50 enemies with a single shot of the Calamity Blade.

Finish off a Cyberdemon with the Pistol.

Reach the end of 'Sigil'.

Kill 4 enemies in 1 shot with the Super Shotgun.

Complete any monster-filled level with 100% kills without taking any damage on Ultra-Violence or higher.

Kill 2 enemies with a single barrel explosion.

Get 100 Chainsaw kills.

Complete 8 different levels sequentially under par time without dying on Ultra-Violence or higher.