Singularity Collapse
Destroy the Citadel's reactor core.
25 ✓ April 2nd, 2011
Escape From City 17
Escape City 17 with Alyx.
20 ✓ April 4th, 2011
Citizen Escort
Don't let any citizens die when escorting them to the escape train.
15 ✓ April 3rd, 2011
Follow Freeman
Gain command of a squad of rebels in the uprising.
10 ✓ March 31st, 2011
Think Fast!
Kill an Elite Soldier with his own energy ball.
10 ✓ April 2nd, 2011
Revenge!
Destroy the hunter-chopper in Half-Life 2.
10 ✓ March 29th, 2011
Bug Hunt
Use the antlions to kill 50 enemies.
10 ✓ March 31st, 2011
Warden Freeman
Survive the second turret standoff in Nova Prospekt.
10 ✓ March 31st, 2011
Plaza Defender
Survive the generator plaza standoff in chapter Anticitizen One.
10 ✓ April 1st, 2011
Fight the Power
Shut down the supression device by disabling its generators.
10 ✓ April 1st, 2011
Giant Killer
Survive the rooftop strider battle in the ruins of City 17.
10 ✓ April 2nd, 2011
Elevator Action
Survive long enough to get on the parking garage elevator.
10 ✓ April 3rd, 2011
Lab Rat
Acquire the fully powered Aperture Science Handheld Portal Device.
5 ✓ April 4th, 2011
Fratricide
Do whatever it takes to survive.
5 ✓ April 4th, 2011
Bone Breaker
Kill 30 enemies with thrown physics objects.
5 ✓ March 30th, 2011
Deadly Harvest
Kill an enemy by planting a hopper mine.
5 ✓ April 1st, 2011
Conservationist
Kill five enemies with the same energy ball.
5 ✓ April 1st, 2011
Grave Robber
Steal a Zombine's grenade.
5 ✓ April 3rd, 2011
Defiant
Hit the trashcan cop with the can.
5 ✓ March 29th, 2011
Malcontent
Escape the apartment block raid.
5 ✓ March 29th, 2011
Trusty Hardware
Get the crowbar.
5 ✓ March 29th, 2011
Anchor's Aweigh!
Get the airboat.
5 ✓ March 29th, 2011
Heavy Weapons
Get the airboat's mounted gun.
5 ✓ March 29th, 2011
Zero-Point Energy
Get the Gravity Gun in Black Mesa East.
5 ✓ March 29th, 2011
Hallowed Ground
Escort Gregori safely through the church cemetery.
5 ✓ March 30th, 2011
OSHA Violation
Kill 3 enemies using the crane.
5 ✓ March 30th, 2011
Where Cubbage Fears to Tread
Defend Little Odessa from the gunship attack.
5 ✓ March 30th, 2011
One Man Army
Destroy six gunships in Half-Life 2.
5 ✓ March 31st, 2011
"Radiation Levels Detected"
Get through the toxic tunnel under City 17 in Half-Life 2.
5 ✓ April 1st, 2011
Watch Your Head!
Make it to the bottom of the Citadel's main elevator shaft in one piece.
5 ✓ April 2nd, 2011
Containment
Contain the Citadel core.
5 ✓ April 3rd, 2011
Attica!
Destroy the gunship in the hospital attic.
5 ✓ April 3rd, 2011
Aperture Science
Earn gold medals on all Portal challenges.
40 
The One Free Bullet
Beat Episode One firing exactly one bullet. Grenade, crowbar, rocket, and Gravgun kills are okay!
40 
Neighborhood Watch
Save all buildings outside the missile silo from destruction.
35 
Little Rocket Man
Send the garden gnome into space.
30 
Vanilla Crazy Cake
Beat all six Portal advanced maps.
30 
Impossible Defense
Successfully defend Gravel Pit without giving up a capture.
30 
Zombie Chopper
Play through Ravenholm using only the Gravity Gun.
25 
🔐 Defense of the Armament
Save the missile silo from the Combine offensive.
20 
Fruitcake
Beat four Portal advanced maps.
20 
Rocket Science
Earn silver medals on all Portal challenges.
20 
Relentless Offense
Win Hydro without giving up a capture.
20 
Keep Off the Sand!
Cross the antlion beach in chapter Sandtraps without touching the sand.
20 
Get Some Grub
Squish every antlion grub in Episode Two.
20 
Puttin' On a Clinic
Defeat the chopper in Episode Two without any misses.
15 
Master of Disguise
Trick an opposing medic into healing you.
15 
Hardcore
Accumulate 1000 total kills.
15 
Lambda Locator
Find all lambda caches in Half-Life 2.
15 
Vorticough
Discover the hidden singing vortigaunt cave in chapter Water Hazard.
13 
🔐 Meet the Hunters
Survive the Hunter ambush with Alyx.
10 
Cache Checker
Find every radar cache in chapter Under The Radar.
10 
🔐 Quiet Mountain Getaway
Survive the ambush at White Forest Inn.
10 
Payback
Kill a Hunter with its own flechettes.
10 
Heartbreaker
Complete Portal.
10 
Cupcake
Beat two Portal advanced maps.
10 
Basic Science
Earn bronze medals on all Portal challenges.
10 
Hard to Kill
Get five kills in a row without dying.
10 
With Friends Like these...
Play in a game with seven or more players from your friends list.
10 
Dynasty
Win 20 games.
10 
Lightning Offense
Win Well in 5 minutes or less.
10 
Impenetrable Defense
Successfully defend Dustbowl without giving up a capture.
10 
Atomizer
Disintegrate 15 soldiers by throwing them into a Combine ball field.
10 
Hot PotatOwned
Kill a Combine soldier with his own grenade.
10 
Blast from the Past
Find the HEV Suit Charger faceplate in Eli's scrapyard.
10 
Pacifist
Contain the Citadel core without killing any stalkers.
10 
Live Bait
Help Alyx snipe 30 enemies in Episode One.
10 
Into the Breach
Help Griggs and Sheckley hold off the antlion invasion inside the mine shaft.
5 
🔐 Twofer
Defeat both antlion guards outside the White Forest.
5 
Hit and Run
Run over 20 enemies with the car in Episode Two.
5 
🔐 Gunishment!
Destroy the Combine cannon in the junkyard.
5 
Gordon Propelled Rocket
Unlock the rocket launcher lambda cache in chapter Under The Radar.
5 
Pedal to the Metal
Beat DOG in a race to the White Forest base.
5 
🔐 Secondary Silo Secured
Secure the launch doors on missile silo 2.
5 
Partygoer
Make the correct party escort submission position decision.
5 
Terminal Velocity
Fall 30,000 feet.
5 
Long Jump
Jump 300 feet.
5 
Turret
Accumulate 10 turret kills with a single turret.
5 
Nemesis
Get five revenge kills.
5 
Powerhouse Offense
Win 2Fort with a shutout.
5 
Head of the Class
Play a complete round with every class.
5 
World Traveler
Play a complete game on every map.
5 
Team Doctor
Accumulate 25000 heal points as a Medic.
5 
Flamethrower
Set five enemies on fire in 30 seconds.
5 
Grey Matter
Get 25 headshots as a Sniper.
5 
Camera Shy
Detach security cameras from the walls.
5 
Friendly Fire
Knock down a turret with another turret.
5 
Hack Attack!
Kill five enemies with a Manhack.
5 
Zombie-que
Use flares to light 15 zombies on fire.
5 
🔐 Submissive
Put the can in the trash.
5 
What cat?
Break the mini-teleporter in Kleiner's lab.
5 
Barnacle Bowling
Kill five barnacles with one barrel.
5 
Targetted Advertising
Pin a soldier to the billboard in chapter Highway 17.
5 
Flushed
Kill an enemy with a toilet.
5 
Counter-Sniper
Kill all of the snipers in City 17.
5 
Car Crusher
Use the cars to squash 15 antlions in Episode One.
5 
Acid Reflex
Kill an acid antlion worker.
5 
Pinata Party
Find and break every web cache in Episode Two.
5 
Two Points
Use DOG's ball to make a basket in Eli's scrapyard.
2