Full list of all 27 Duke Nukem 3D: 20th Anniversary World Tour achievements. It takes around 12-15 hours to unlock all of the achievements on Windows.
Kill every enemy on a level.
Carry all weapons with ammo at once.
Use a cheat code.
Listen to Developer Commentary (Use at least one trigger).
Step in a pile of excrement.
Find the Doomguy in the Level "Death Row".
Tip an exotic dancer.
Finish the "Hollywood Holocaust" level in under 3 minutes.
Find a secret area.
Complete "L.A. Meltdown" on any difficulty.
Complete "Lunar Apocalypse" on any difficulty.
Complete "Shrapnel City" on any difficulty.
Complete "The Birth" on any difficulty.
Complete "Alien World Order" on any difficulty.
Step on 40 enemies after using the Shrinker on them.
Find 70 secret areas.
Kill 1000 enemies.
Find Luke in the Level "Lunar Reactor".
Find Sam in "Mirage Barrage".
Use the hookah in High Times.
Finish any level on "Damn, I'm Good" difficulty.
Find any secret level.
Use the Incinerator
Burn 50 bad guys to death.
Kill a Firefly Trooper while it's flying small.
Kill 5 bad guys with one shot.
Kill 10 bad guys in 10 seconds while on steroids.