Here is the full list of all 27 Duke Nukem 3D: 20th Anniversary Edition World Tour achievements worth 1,000 gamerscore.
Use a cheat code.
Complete "Alien World Order" on any difficulty.
Carry all weapons with ammo at once.
Find Sam in "Mirage Barrage".
Burn 50 bad guys to death.
Use the Incinerator
Kill a Firefly Trooper while it's flying small.
Use the hookah in High Times.
Complete "The Birth" on any difficulty.
Complete "Shrapnel City" on any difficulty.
Step in a pile of excrement.
Complete "Lunar Apocalypse" on any difficulty.
Find Luke in the Level "Lunar Reactor"
Kill 1000 enemies.
Find 70 secret areas.
Step on 40 enemies after using the Shrinker on them.
Kill 5 bad guys with one shot.
Kill 10 bad guys in 10 seconds while on steroids.
Finish any level on "Damn, I'm Good" difficulty.
Finish the "Hollywood Holocaust" level in under 3 minutes.
Complete "L.A. Meltdown" on any difficulty.
Finish a secret level.
Find the Doomguy in the Level "Death Row"
Tip an exotic dancer.
Kill every enemy on a level.
Find a secret area.
Listen to Developer Commentary (Use at least one trigger).