Unlocked: Feb 26, 2012 11:16am
Hit the trashcan cop with the can.
Unlocked: Feb 26, 2012 11:28am
Escape the apartment block raid.
Unlocked: Apr 10, 2012 2:26pm
Get the airboat.
Unlocked: Apr 22, 2012 8:57am
Get the airboat's mounted gun.
Unlocked: Apr 22, 2012 9:34am
Destroy the hunter-chopper in Half-Life 2.
Unlocked: Apr 26, 2012 10:23am
Blast from the Past
Find the HEV Suit Charger faceplate in Eli's scrapyard.
Unlocked: Apr 26, 2012 10:24am
Get the Gravity Gun in Black Mesa East.
Unlocked: Apr 30, 2012 6:14pm
Escort Gregori safely through the church cemetery.
Unlocked: May 3, 2012 11:39am
Kill 3 enemies using the crane.
Unlocked: May 3, 2012 11:28am
Where Cubbage Fears to Tread
Defend Little Odessa from the gunship attack.
Unlocked: May 23, 2012 3:09pm
One Man Army
Destroy six gunships in Half-Life 2.
Unlocked: May 13, 2012 2:33pm
Use the antlions to kill 50 enemies.
Unlocked: May 17, 2012 11:44am
Survive the second turret standoff in Nova Prospekt.
Unlocked: May 17, 2012 12:07pm
Gain command of a squad of rebels in the uprising.
Unlocked: May 22, 2012 3:31pm
Radiation Levels Detected
Get through the toxic tunnel under City 17 in Half-Life 2.
Unlocked: May 22, 2012 4:02pm
Survive the generator plaza standoff in chapter Anticitizen One.
Unlocked: May 23, 2012 2:53pm
Fight the Power
Shut down the supression device by disabling its generators.
Unlocked: May 23, 2012 3:56pm
Survive the rooftop strider battle in the ruins of City 17.
Unlocked: May 24, 2012 7:40pm
Disintegrate 15 soldiers by throwing them into a Combine ball field.
Unlocked: May 29, 2012 5:24pm
Destroy the Citadel's reactor core.
Break the mini-teleporter in Kleiner's lab.
Get the crowbar.
Kill five barnacles with one barrel.
Discover the hidden singing vortigaunt cave in chapter Water Hazard.
Use DOG's ball to make a basket in Eli's scrapyard.
Play through Ravenholm using only the Gravity Gun.
Pin a soldier to the billboard in chapter Highway 17.
Keep Off the Sand!
Cross the antlion beach in chapter Sandtraps without touching the sand.
Kill an enemy with a toilet.
Kill all of the snipers in City 17.
Find all lambda caches in Half-Life 2.
Kill five enemies with a Manhack.