Relentless Offense – 20 points.
Win Hydro without giving up a capture.
Revenge! – 10 points.
Destroy the hunter-chopper in Half-Life 2.
Rocket Science – 20 points.
Earn silver medals on all Portal challenges.
Secondary Silo Secured – 5 points.
Secure the launch doors on missile silo 2.
Submission – 5 points.
Put the trash in the garbage can in HL2.
Targetted Advertising – 5 points.
Pin a soldier to the billboard in chapter Highway 17.
Team Doctor– 5 points.
Accumulate 25000 heal points as a Medic.
Terminal Velocity – 5 points.
Fall 30,000 feet.
The One Free Bullet – 40 points.
Beat Episode One firing exactly one bullet. Grenade, crowbar, rocket, and Gravgun kills are okay!
Think Fast! – 10 points.
Kill an Elite Soldier with his own energy ball.
Trusty Hardware – 5 points.
Get the crowbar.
Turret – 5 points.
Accumulate 10 turret kills with a single turret.
Two Points – 2 points.
Use DOG’s ball to make a basket in Eli’s scrapyard.
Twofer– 5 points.
Defeat both antlion guards outside the White Forest
Vanilla Crazy Cake – 30 points.
Beat all six Portal advanced maps.
Vorticough – 13 points.
Discover the hidden singing vortigaunt cave in chapter Water Hazard.
Warden Freeman – 10 points.
Survive the second turret standoff in Nova Prospekt.
Watch Your Head! – 5 points.
Make it to the bottom of the Citadel’s main elevator shaft in one piece.
What cat? – 5 points.
Break the mini-teleporter in Kleiner’s lab.
Where Cubbage Fears to Tread – 5 points.
Defend Little Odessa from the Gunship Attack
With Friends Like these… – 10 points.
Play in a game with seven or more players from your friends list.
World Traveler – 5 points.
Play a complete game on every map.
Zero-Point Energy – 5 points.
Get the Gravity Gun in Black Mesa East.
Zombie Chopper – 25 points.
Play through Ravenholm using only the Gravity Gun.
Zombie-que – 5 points.
Use flares to light 15 zombies on fire.