Bone Breaker (5 points)
Kill 30 enemies with thrown physics objects.

Deadly Harvest (5 points)
Kill an enemy by planting a hopper mine.

Hack Attack! (5 points)
Kill five enemies with a Manhack.

Hot PotatOwned (10 points)
Kill a Combine soldier with his own grenade.

Conservationist (5 points)
Kill five enemies with the same energy ball.

Think Fast! (10 points)
Kill an Elite Soldier with his own energy ball.

Grave Robber (5 points)
Steal a Zombine's grenade.

Zombie-que (5 points)
Use flares to light 15 zombies on fire.

Malcontent (5 points)
Escape the apartment block raid.

What cat? (5 points)
Break the mini-teleporter in Kleiner's lab.

Trusty Hardware (5 points)
Get the crowbar.

Barnacle Bowling (5 points)
Kill five barnacles with one barrel.

Anchor's Aweigh! (5 points)
Get the airboat.

Heavy Weapons (5 points)
Get the airboat's mounted gun.

Vorticough (13 points)
Discover the hidden singing vortigaunt cave in chapter Water Hazard.

Revenge! (10 points)
Destroy the hunter-chopper in Half-Life 2.

Blast from the Past (10 points)
Find the HEV Suit Charger faceplate in Eli's scrapyard.

Zero-Point Energy (5 points)
Get the Gravity Gun in Black Mesa East.

Two Points (2 points)
Use DOG's ball to make a basket in Eli's scrapyard.

Zombie Chopper (25 points)
Play through Ravenholm using only the Gravity Gun.

OSHA Violation (5 points)
Kill 3 enemies using the crane.

Targetted Advertising (5 points)
Pin a soldier to the billboard in chapter Highway 17.

One Man Army (5 points)
Destroy six gunships in Half-Life 2.

Keep Off the Sand! (20 points)
Cross the antlion beach in chapter Sandtraps without touching the sand.

Bug Hunt (10 points)
Use the antlions to kill 50 enemies.

Flushed (5 points)
Kill an enemy with a toilet.

Warden Freeman (10 points)
Survive the second turret standoff in Nova Prospekt.

"Radiation Levels Detected" (5 points)
Get through the toxic tunnel under City 17 in Half-Life 2.

Plaza Defender (10 points)
Survive the generator plaza standoff in chapter Anticitizen One.

Counter-Sniper (5 points)
Kill all of the snipers in City 17.

Fight the Power (10 points)
Shut down the supression device by disabling its generators.

Giant Killer (10 points)
Survive the rooftop strider battle in the ruins of City 17.

Lambda Locator (15 points)
Find all lambda caches in Half-Life 2.

Watch Your Head! (5 points)
Make it to the bottom of the Citadel's main elevator shaft in one piece.

Containment (5 points)
Contain the Citadel core.

Pacifist (10 points)
Contain the Citadel core without killing any stalkers.

Car Crusher (5 points)
Use the cars to squash 15 antlions in Episode One.

Elevator Action (10 points)
Survive long enough to get on the parking garage elevator.

Live Bait (10 points)
Help Alyx snipe 30 enemies in Episode One.

Attica! (5 points)
Destroy the gunship in the hospital attic.

Citizen Escort (15 points)
Don't let any citizens die when escorting them to the escape train.

Escape From City 17 (20 points)
Escape City 17 with Alyx.

The One Free Bullet (40 points)
Beat Episode One firing exactly one bullet. Grenade, crowbar, rocket, and Gravgun kills are okay!

Acid Reflex (5 points)
Kill an acid antlion worker.

Get Some Grub (20 points)
Squish every antlion grub in Episode Two.

Pinata Party (5 points)
Find and break every web cache in Episode Two.

Into the Breach (5 points)
Help Griggs and Sheckley hold off the antlion invasion inside the mine shaft.

Hit and Run (5 points)
Run over 20 enemies with the car in Episode Two.

Puttin' On a Clinic (15 points)
Defeat the chopper in Episode Two without any misses.

Cache Checker (10 points)
Find every radar cache in chapter Under The Radar.

Gordon Propelled Rocket (5 points)
Unlock the rocket launcher lambda cache in chapter Under The Radar.

Pedal to the Metal (5 points)
Beat DOG in a race to the White Forest base.

Little Rocket Man (30 points)
Send the garden gnome into space.

Neighborhood Watch (35 points)
Save all buildings outside the missile silo from destruction.

Payback (10 points)
Kill a Hunter with its own flechettes.

Lab Rat (5 points)
Acquire the fully powered Aperture Science Handheld Portal Device.

Fratricide (5 points)
Do whatever it takes to survive.

Partygoer (5 points)
Make the correct party escort submission position decision.

Heartbreaker (10 points)
Complete Portal.

Terminal Velocity (5 points)
Fall 30,000 feet.

Long Jump (5 points)
Jump 300 feet.

Cupcake (10 points)
Beat two Portal advanced maps.

Fruitcake (20 points)
Beat four Portal advanced maps.

Vanilla Crazy Cake (30 points)
Beat all six Portal advanced maps.

Basic Science (10 points)
Earn bronze medals on all Portal challenges.

Rocket Science (20 points)
Earn silver medals on all Portal challenges.

Aperture Science (40 points)
Earn gold medals on all Portal challenges.

Turret (5 points)
Accumulate 10 turret kills with a single turret.

Nemesis (5 points)
Get five revenge kills.

Hard to Kill (10 points)
Get five kills in a row without dying.

Master of Disguise (15 points)
Trick an opposing medic into healing you.

With Friends Like these... (10 points)
Play in a game with seven or more players from your friends list.

Dynasty (10 points)
Win 20 games.

Hardcore (15 points)
Accumulate 1000 total kills.

Powerhouse Offense (5 points)
Win 2Fort with a shutout.

Lightning Offense (10 points)
Win Well in 5 minutes or less.

Relentless Offense (20 points)
Win Hydro without giving up a capture.

Impenetrable Defense (10 points)
Successfully defend Dustbowl without giving up a capture.

Impossible Defense (30 points)
Successfully defend Gravel Pit without giving up a capture.

Head of the Class (5 points)
Play a complete round with every class.

World Traveler (5 points)
Play a complete game on every map.

Team Doctor (5 points)
Accumulate 25000 heal points as a Medic.

Flamethrower (5 points)
Set five enemies on fire in 30 seconds.

Atomizer (10 points)
Disintegrate 15 soldiers by throwing them into a Combine ball field.

Follow Freeman (10 points)
Gain command of a squad of rebels in the uprising.

Grey Matter (5 points)
Get 25 headshots as a Sniper.

Camera Shy (5 points)
Detach security cameras from the walls.

Friendly Fire (5 points)
Knock down a turret with another turret.


Secret Achievements

 

Submissive (5 points)
Put the can in the trash.

Defiant (5 points)
Hit the trashcan cop with the can.

Hallowed Ground (5 points)
Escort Gregori safely through the church cemetery

Where Cubbage Fears to Tread (5 points)
Defend Little Odessa from the Gunship Attack

Singularity Collapse (25 points)
Destroy the Citadel's reactor core.

Twofer (5 points)
Defeat both antlion guards outside the White Forest.

Meet the Hunters (10 points)
Survive the Hunter ambush with Alyx.

Gunishment! (5 points)
Destroy the Combine cannon in the junkyard.

Quiet Mountain Getaway (10 points)
Survive the ambush at White Forest Inn.

Secondary Silo Secured (5 points)
Secure the launch doors on missile silo 2.

Defense of the Armament (20 points)
Save the missile silo from the Combine offensive