Unlocked: Aug 25, 2012 1:25pm
Hit the trashcan cop with the can.
Unlocked: Aug 25, 2012 1:42pm
Escape the apartment block raid.
Unlocked: Aug 25, 2012 1:55pm
Get the crowbar.
Unlocked: Aug 25, 2012 3:28pm
Get the airboat.
Unlocked: Aug 26, 2012 12:07pm
Get the airboat's mounted gun.
Unlocked: Aug 26, 2012 12:19pm
Destroy the hunter-chopper in Half-Life 2.
Unlocked: Aug 28, 2012 7:20am
Pin a soldier to the billboard in chapter Highway 17.
Unlocked: Aug 27, 2012 10:42am
Where Cubbage Fears to Tread
Defend Little Odessa from the gunship attack.
Unlocked: Feb 18, 2013 10:25am
One Man Army
Destroy six gunships in Half-Life 2.
Unlocked: Feb 18, 2013 10:36am
Use the antlions to kill 50 enemies.
Break the mini-teleporter in Kleiner's lab.
Kill five barnacles with one barrel.
Discover the hidden singing vortigaunt cave in chapter Water Hazard.
Blast from the Past
Find the HEV Suit Charger faceplate in Eli's scrapyard.
Get the Gravity Gun in Black Mesa East.
Use DOG's ball to make a basket in Eli's scrapyard.
Play through Ravenholm using only the Gravity Gun.
Kill 3 enemies using the crane.
Keep Off the Sand!
Cross the antlion beach in chapter Sandtraps without touching the sand.
Kill an enemy with a toilet.
Survive the second turret standoff in Nova Prospekt.
Gain command of a squad of rebels in the uprising.
Radiation Levels Detected
Get through the toxic tunnel under City 17 in Half-Life 2.
Survive the generator plaza standoff in chapter Anticitizen One.
Kill all of the snipers in City 17.
Fight the Power
Shut down the supression device by disabling its generators.
Survive the rooftop strider battle in the ruins of City 17.
Disintegrate 15 soldiers by throwing them into a Combine ball field.
Find all lambda caches in Half-Life 2.
Kill five enemies with a Manhack.