Stop a squad member from suffocating in single player
Eliminate all alien waves
Complete Deluge
Jump two stories in one move in single player
Make certain of the new threat's location
Deal with the newest global threat
Eradicate the infestation
Beat a new special mission without losing any assets
Get a Soldier to have 5 modifications in single player
Cause an enemy to suicide
Use Collateral Damage to blow up a car in single player
Modify a soldier in single player
Have your special-duty soldier kill three enemies in the same mission
Eliminate an enemy's shield and kill it on the same turn in single player
Field a fully enhanced squad and win the mission
Deploy three tactical subsystems on a single soldier in single player
Kill a Muton Berserker in melee combat in single player
Kill an elite enemy Medic with explosive damage in single player
Get at least 4 kills with XCOM Base Security personnel
Proc Combat Rush on the entire squad (min. 4)
Kill an elite enemy Sniper with one of your own snipers in single player
Complete Furies
Kill an unseen enemy detected by a specially modified soldier in single player
Kill an enemy as it is psionically attacking you in single player
Field a squad where all members have at least two modifications (min. 4) and win the mission
Field a squad consisting entirely of augmented soldiers and SHIVs (min. 4) and win the mission
Augment a soldier in single player
Designate a highly decorated soldier as the Volunteer
Field a squad with 4 augmented soldiers, each with a different base ability and win the mission
Beat the game without buying a Squad Size upgrade (Classic+ difficulty)
Complete a mission without losing a soldier.
Recover the Hyperwave Beacon.
Launch a Satellite.
Build an item.
Capture a live alien.
Successfully assault an Overseer UFO.
Build a S.H.I.V.
Advance one of your soldiers to Colonel rank.
Build a Laboratory.
Build a base facility.
Find a soldier with the Gift.
Complete a Research Project.
Stun an Outsider.
Complete the tutorial mission.
Build a Workshop.
Shoot down a UFO.
Fulfill a Council request.
Earn the "Excellent" rating in every performance category on a terror mission.
Kill 500 aliens.
Build a suit of powered armor.
Staff the Engineering Department with 80 engineers.
Kill 50 aliens with explosive weapons.
In a single game, shoot down one of each alien craft.
Staff the Research Labs with 80 scientists.
In a single game, complete every Foundry project.
Beat the game on any difficulty.
Gain access to the lowest level in your base.
Make contact with the Ethereal hive mind.
Win a multiplayer match.
Get satellite coverage over every country on one continent.
In a single game, complete every Research Project.
Acquire 1000 credits in one month.
In a single game, complete every Autopsy.
Build the Gollop Chamber.
Kill 150 aliens.
Kill an alien while flying. Single player only.
Mind Control an Ethereal. Single player only.
Win a mission with an all-female squad. Single player only.
Play a multiplayer match against someone with this achievement.
Complete a Very Hard abduction mission in five turns or less on Classic or Impossible difficulty.
Beat the game in Ironman mode on Classic or Impossible Difficulty.
Shoot down 40 UFOs.
Clear a UFO crash site with one soldier on Classic or Impossible difficulty.
Uncover the alien base's location.
Have a soldier survive every mission in a full game.
Build a Firestorm.
Build the Hyperwave Relay.
Beat the game on Classic difficulty.
Win the game from each of the 5 starting locations.
Beat the game on Impossible difficulty.
Complete Friends in Low Places.
Complete Confounding Light.
Complete Gangplank.
Complete Confounding Light with more than 3 turns left on the timer.
Take your new ally into the final challenge.