Reach the end of 'DOOM'.
Gib three or more enemies with a single rocket explosion.
Crush a corpse in a door.
Get 25 kills with your Fists in a single level.
Get 20 kills using the berserk powerup in a single level.
Finish off a Cyberdemon with the Pistol.
Find a secret area.
Cause an enemy to kill another enemy.
Kill 2 enemies with a single barrel explosion.
Finish a level with 200% armor and 200% health.
Kill one of every enemy.
Complete a level on Nightmare difficulty.
Finish a level with 100% items picked up.
Complete any monster-filled level with 100% kills without getting hurt on Ultra-Violence or higher.
Find a secret level.
Get 100 Chainsaw kills.
Kill all monsters in any monster-filled level on 'Hurt me plenty' or higher.
Complete any monster-filled level with 100% kills, items, and secrets.
Complete 8 different levels sequentially under par time without dying on Ultra-Violence or higher.
Immolate a total of 30 arachnoid enemies with the Incinerator.
Obliterate 50 enemies with a single shot of the Calamity Blade.
Reach the end of 'Sigil'.
Reach the end of 'DOOM II'.
Reach the end of 'No Rest for the Living'.
Reach the end of 'Master Levels for DOOM II'.
Reach the end of 'TNT: Evilution'.
Reach the end of 'The Plutonia Experiment'.
Reach the end of 'Legacy of Rust'.
Get 3 multi-kills with the Shotgun.
Kill 4 enemies in 1 shot with the Super Shotgun.
Shoot 200 bullets consecutively with the Chaingun.
Kill 5 enemies in 5 seconds with the Plasma Rifle.
Kill only a single enemy with a BFG9000 blast.
