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