Use the flamethrower
Cause the Alien to retreat by using the flamethrower
Complete the third mission
Encounter the Alien in Sevastopol for the first time
Collect an ID tag
Complete the second mission
Construct an item
Complete the first mission
Collect an archive log
Complete the fourth mission
Complete the fifth mission
Complete the sixth mission
Complete the seventh mission
Use the stun baton
Complete the tenth mission
Complete the eleventh mission
Complete the twelfth mission
Complete the thirteenth mission
Complete the game on the hardest difficulty setting
Complete the game on any difficulty setting
Collect all ID tags
Collect 10 Nostromo logs in the main campaign
Contact your team and escape Comms without being attacked by an android
Use the shotgun
Use the revolver
Kill 10 humans
Escape from android combat without taking damage
Cause the Alien to retreat using a molotov
Use the vent system 20 times
Detect 30 targets with the motion tracker
Knock down a human or stun an android with a non-lethal attack
Complete the game without killing any humans
Navigate Reactor Maintenance without dying
Perform 10 successful hacks
Complete 10 minigames successfully
Access 10 different rewire points
Construct one of each craftable item
Collect 100 archive logs
Kill an Android
Complete the seventeenth mission
Complete the eighteenth mission
Use the bolt gun
Kill an android using only the maintenance jack
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