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