What cat? (5G)
Break the mini-teleporter in Kleiner's lab.
Aug 8, 08
Make the correct party escort submission position decision.
Lab Rat (5G)
Acquire the fully powered Aperture Science Handheld Portal Device.
Secret Achievements (75G)
1 out of 8 achieved are secret achievements
Disintegrate 15 soldiers by throwing them into a Combine ball field.
Giant Killer (10G)
Survive the rooftop strider battle in the ruins of City 17.
Think Fast! (10G)
Kill an Elite Soldier with his own energy ball.
Fight the Power (10G)
Shut down the supression device by disabling its generators.
Plaza Defender (10G)
Survive the generator plaza standoff in chapter Anticitizen One.
Follow Freeman (10G)
Gain command of a squad of rebels in the uprising.
Warden Freeman (10G)
Survive the second turret standoff in Nova Prospekt.
Beat four Portal advanced maps.
Bug Hunt (10G)
Use the antlions to kill 50 enemies.
Keep Off the Sand! (20G)
Cross the antlion beach in chapter Sandtraps without touching the sand.
Bone Breaker (5G)
Kill 30 enemies with thrown physics objects.
Discover the hidden singing vortigaunt cave in chapter Water Hazard.
Beat two Portal advanced maps.
Two Points (2G)
Use DOG's ball to make a basket in Eli's scrapyard.
Destroy the hunter-chopper in Half-Life 2.
Use flares to light 15 zombies on fire.
Zombie Chopper (25G)
Play through Ravenholm using only the Gravity Gun.
Kill an enemy with a toilet.
Watch Your Head! (5G)
Make it to the bottom of the Citadel's main elevator shaft in one piece.
Contain the Citadel core without killing any stalkers.
Car Crusher (5G)
Use the cars to squash 15 antlions in Episode One.
Elevator Action (10G)
Survive long enough to get on the parking garage elevator.
Live Bait (10G)
Help Alyx snipe 30 enemies in Episode One.
Destroy the gunship in the hospital attic.
Citizen Escort (15G)
Don't let any citizens die when escorting them to the escape train.
The One Free Bullet (40G)
Beat Episode One firing exactly one bullet. Grenade, crowbar, rocket, and...
Pinata Party (5G)
Find and break every web cache in Episode Two.
Into the Breach (5G)
Help Griggs and Sheckley hold off the antlion invasion inside the mine shaft.
Hit and Run (5G)
Run over 20 enemies with the car in Episode Two.
Cache Checker (10G)
Find every radar cache in chapter Under The Radar.
Kill a Hunter with its own flechettes.
Accumulate 10 turret kills with a single turret.
Get five revenge kills.
Accumulate 1000 total kills.
Team Doctor (5G)
Accumulate 25000 heal points as a Medic.
Camera Shy (5G)
Detach security cameras from the walls.