Complete a Research Project.

Complete a mission without losing a soldier.

Build an item.

Complete the tutorial mission.

Continue playing to unlock this secret achievement.

Get satellite coverage over every country on one continent.

Build a suit of powered armor.

Continue playing to unlock this secret achievement.

Build a base facility.

Continue playing to unlock this secret achievement.

Advance one of your soldiers to Colonel rank.

Continue playing to unlock this secret achievement.

Continue playing to unlock this secret achievement.

Staff the Engineering Department with 80 engineers

Continue playing to unlock this secret achievement.

Continue playing to unlock this secret achievement.

Continue playing to unlock this secret achievement.

Fulfill a Council request.

Build a Workshop.

Staff the Research Labs with 80 scientists.

Continue playing to unlock this secret achievement.

Build a S.H.I.V.

Acquire 1000 credits in one month.

Continue playing to unlock this secret achievement.

In a single game, complete every Autopsy.

Launch a Satellite.

Shoot down a UFO.

Kill 150 aliens.

Beat the game on any difficulty.

Continue playing to unlock this secret achievement.

Kill 50 aliens with explosive weapons.

Build a Laboratory.

Kill 500 aliens.

Earn the "Excellent" rating in every performance category on a terror mission.

Gain access to the lowest level in your base.

In a single game, complete every Research Project.

Continue playing to unlock this secret achievement.

Shoot down 40 UFOs.

Complete Friends in Low Places.

In a single game, shoot down one of each alien craft.

In a single game, complete every Foundry project.

Complete Gangplank.

Complete Confounding Light.

Beat the game in Ironman mode on Classic or Impossible difficulty.

Take your new ally into the final challenge.

Complete Confounding Light with more than 3 turns left on the timer.

Continue playing to unlock this secret achievement.

Clear a UFO crash site with one soldier on Classic or Impossible difficulty.

Continue playing to unlock this secret achievement.

Have a soldier survive every mission in a full game.

Beat the game on Impossible difficulty.

Beat the game on Classic difficulty.

Win the game from each of the 5 starting locations.

Complete a Very Hard abduction mission in five turns or less on Classic or Impossible difficulty.

Continue playing to unlock this secret achievement.