Here is the full list of all 50 Duke Nukem Forever (RU) achievements.
Find all 3 helmets in the SP campaign
Listen to all phone messages
Complete the SP campaign on Hard Difficulty
Complete the SP campaign on Insane Difficulty
Kill all of the catfish in the underwater level
Unlock the secret closet at the end of the Forkstop
Kill 15 frozen aliens
Look at every page of a calendar in SP
Discover all ego cap rewards
Drink all of the beers in the strip club
Get hit by 10 Pregnator bombs
Kill 15 aliens with melee attacks while on steroids
Kill 10 aliens with tossed objects
Watch the credits all the way through
Carry the gold pistol through the whole SP campaign
Complete the SP campaign on Easy Difficulty
Complete the SP campaign on Normal Difficulty
Get knocked down 10 times
Defeat the Energy Leech
Defeat the Octaking
Kill 6 aliens with the forklift
Execute 20 aliens
Defeat the Battlelord on the Hoover Dam
Kill 10 aliens with Trip Mines
Kill 15 aliens with the monster truck
Foot stomp 12 aliens
Use a Holoduke in SP
Blow up 5 enemy gunships or dropships
Shoot down 20 alien fighters
Win a game of Alien Abortion in the strip club
Win air hockey with a score of 7-0 in the strip club
Defeat the Alien Queen
Kill 250 aliens
Kill 30 aliens with headshots
Kill 10 aliens with environmental explosives
Defeat the Battlelord in Las Vegas
Kill 100 aliens
Put a Trip Mine on a live alien
Kill 50 aliens
Kill 3 aliens at once
Drink beer while on steroids or vice-versa in SP
Take steroids in SP
Drink a beer in SP
Earn a 1,000,000 pinball score in SP
Knock out the talent at the talk show
Eat 10 pieces of food during the SP campaign
Defeat the Cycloid
Shoot down the blimp above the stadium
Doodle something on the whiteboard in SP
Find and steal a piece of poo