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