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