Containment
Not unlocked yetContain the Citadel core.
Pacifist
Not unlocked yetContain the Citadel core without killing any stalkers.
Citizen Escort
Not unlocked yetDon't let any citizens die when escorting them to the escape train.
Escape From City 17
Not unlocked yetEscape City 17 with Alyx.
The One Free Bullet
Not unlocked yetFinish the game firing exactly one bullet. Grenade, crowbar, rocket, and Gravity Gun kills are okay!
Elevator Action
Not unlocked yetSurvive long enough to get on the parking garage elevator.
Attica!
Not unlocked yetDestroy the gunship in the hospital attic.
Watch Your Head!
Not unlocked yetMake it to the bottom of the Citadel's main elevator shaft in one piece.
Car Crusher
Not unlocked yetUse the cars to squash 15 antlions in Episode One.
Live Bait
Not unlocked yetHelp Alyx snipe 30 enemies in Episode One.
Zombie-que
Not unlocked yetUse flares to light 15 zombies on fire.
Think Fast!
Not unlocked yetKill an Elite Soldier with his own energy ball.
Conservationist
Not unlocked yetKill five enemies with the same energy ball.