Full list of all 46 Aliens: Fireteam Elite achievements worth 1,115 gamerscore. It takes around 100-120 hours to unlock all of the achievements in the base game.
The base game contains 42 achievements worth 1,000 Gamerscore, and there are 2 DLC packs containing 4 achievements worth 115 Gamerscore.
Finish a mission on Intense Difficulty.
Collected one attachment of every type on a single character.
Change your hat and outfit.
Eliminate 300 Pathogen.
Equip three attachments on a single weapon.
Kill 50 enemies with explosive barrels or pods.
Finish all Campaigns on Standard Difficulty.
Finish the "Only Way to be Sure" Campaign.
Level a weapon to four stars.
Collected 25 attachments on a single character.
Finish the "Gift of Fire" Campaign.
Finish the "Giants in the Earth" Campaign.
Get grappled five times in the same mission.
Equip a colorway and decal onto a gun.
Finish the "Priority One" Campaign.
Do a successful Challenge run.
Finish a mission on Extreme Difficulty.
Finish a mission on Insane Difficulty.
Finish all Campaigns on Intense Difficulty.
Finish all Campaigns on Extreme Difficulty.
Finish all Campaigns on Insane Difficulty.
Return 39 pieces of intel on a single character.
Open 50 hidden caches.
Complete 25 successful Challenge runs.
Level a Kit to Rank 8.
Level five Kits to Rank 8 on a single character.
Level 30 weapons to four stars on a single character.
Fill every slot in a perk board.
Eliminate 1000 Synthetics.
Eliminate 10000 Xenomorphs.
Eliminate 2000 elite enemies.
Kill 1000 enemies with fire.
Kill 1000 enemies with electricity.
Collect 20 emotes on a single character.
Collect 20 hats on a single character.
Collect 40 decals on a single character.
Collect 40 weapon colors on a single character.
Use 500 consumables.
Complete 50 missions without anyone being downed.
Complete a mission on Intense Difficulty or above without anyone taking friendly fire damage.
Complete a mission without using aid kits, ammo crates, or consumables.
Heal your fireteam with an aid kit 100 times.
Finish the "Promise of a Flower" Campaign.
Return 48 pieces of intel on a single character.
Destroy 50 explosive spore pods with Weapons or Abilities.
Finish a mission on Hardcore 10 Difficulty.