Here is the full list of all 50 Aliens vs. Predator achievements.
Complete all three Campaigns
Complete Alien Campaign on Hard difficulty setting
Create a new species
Destroy all 50 Royal Jelly Containers
Harvest all available civilians in the Alien Campaign
Solve the riddle of the Ruins
Wipe out all of the Marines in the Colony
Kill 10 enemies with head shots from the scoped rifle
Kill two enemies with one throw of the Battle Disc
Complete Predator Campaign on Hard difficulty setting
Destroy the Abomination
Find all 45 Predator trophy belts
Retrieve the second artifact
Kill 20 enemies with the Combi Stick
Find a way into the Research Lab
Survive trial by combat
Retrieve the ancient mask
Complete Marine Campaign on Hard difficulty setting
Discover all 67 Audio Diaries
Kill 5 enemies with one burst from the smartgun
Kill 30 enemies with the pistol
Kill 2 enemies with one shot with the shotgun
Escape from the Research Lab
Liberate the Matriarch
Discover the Elite Predator's fate
Heal or regenerate 30 blocks of health in Survivor
Recover Weyland's datapad
Escape from C-Block
Get all the Aliens vs Predator achievements
Survive The 'Party' at The Club
Help Van Zandt
Defeat the Matriarch
Locate Tequila
Get Tequila to surgery
Defeat the Praetorian
Find a way through Gateway
Find the Youngbloods in the Jungle
Complete Marine Campaign on Nightmare difficulty setting
Complete Alien Campaign on Nightmare difficulty setting
Complete Predator Campaign on Nightmare difficulty setting
As a team, kill 20 enemies in under 60 seconds in a Survivor match.
Play and complete your first Ranked Match in standard Deathmatch mode
Win your first Ranked Match in standard Deathmatch mode
Win 10 Ranked Matches in any Deathmatch mode
Kill 10 enemies in a row without dying in a Ranked Match
Achieve Persecutor status more than once in any Ranked Match
Play with six friends in a Ranked Match
Finish a Ranked Infestation match as the only remaining prey
Get 6000 XP in Ranked Matches
Get 18060 XP in Ranked Matches