Assassin's Creed (franchise)
Battlefield Bad Company 2 (franchise)
Borderlands (franchise)
Dawn of War II: Retribution
Grand Theft Auto IV: Complete Edition
Fable III (DLCs too!)
Fallout New Vegas (franchise)
Just Cause 2 (franchise)
Magicka (DLCs too!)
Portal 2
Sanctum
Terraria
Total War: SHOGUN 2 (DLC too!)
Two Worlds II
The Witcher 2
Dead Space Franchise
Portal II
F1 2010
Prince of Persia Complete Pack
Duke Nukem
Hitman Collection
Supreme Commander 2
Sam & Max Franchise
X3: Terran Conflict and X Superbox
NeverWinterNights Platinum
Post Apocalyptic Mayhem
Terraria
activities
Post Apocalyptic Mayhem
Summer Jam - Adjust a Tuning Slider and save the new setting
X3: Terran Conflict
Solar Shock Wave - Destroy a Solar Power Plant
Portal 2
Talent Show - Never lose a cube in Chamber 6 of the Mobility Gels co-op course
Hydrophobia: Prophecy
Put another shrimp on the barby - Player must use the environment to take down 3 Malthusians with fire!
Nimbus
Precision BBQ - Bump the meat onto the grill on World 2-4!
Serious Sam HD: The Second Encounter
Treasure diving - Find a secret under water
Altitude
Electric Firefighter - Interrupt an enemy's afterburners with Loopy's EMP grenade. Easy peasy lemon squeezy.
Turba
Summer Block Party - In one combo, clear at least 5 blocks of each color, 2 silver blocks and 1 bomb block. Those red blocks are real party animals.
Honest feedback - Post a comment on a friend's screenshot
Mafia Franchise
Worms Reloaded
Red Faction: Armageddon
Mass Effect Franchise
Fallout 3 Game of the Year
Divinity II - Dragon Knight Saga
Splinter Cell Collector Pack
Empire Total War
Napoleon Total War
DiRT 3
The Last Remnant
Universe Sandbox
Amnesia: The Dark Descent
activities
Universe Sandbox
Heat Wave - Plunge the Earth into the Sun
Worms Reloaded
Summer of 69 - Take exactly 31 damage from a worm with 100 health.
Doc Clock: The Toasted Sandwich of Time
Hot And Bothered - Fall into a pit of lava 3 times
1... 2... 3... KICK IT! (Drop That Beat Like an Ugly Baby)
I Beat City 15 - Get 75%+ of the maximum score AND 50,000+ points with any song on City 15
Galcon Fusion
Pool Party - Win 5 Rounds in Multi-player Billiards
Winter Voices
Summer's Gone, But A Lot Goes On - Achieve a 100% success in the third encounter of the prologue (departure of the father), after walking on the 'Summer Scent'
Warhammer 40,000: Dawn of War II: Retribution
Summer Slaying - Kill 5 Banshees in the Bloodied Colloseum
Day of Defeat: Source
Beat the Heat - Win a round on each of the winter themed maps: Dod_Kalt and Dod_Colmar
Wish upon a star - Build a wishlist of 10 items
Show time - Post your own video in Steam
Street Fighter IV
Rift
Lara Croft and the Guardian of Light
Tomb Raider Franchise
Command & Conquer Franchise
Dead Rising 2
Quake Collection
Counter Strike
Cities XL 2011
Company of Heroes Complete Pack
Risen
Audiosurf
Sanctum
activities
Sanctum
Beach Party - Start the party on Glade
AudioSurf
Sunburn - Turn 21 blocks red with a single paint
Counter-Strike: Source
Happy Camper - Get 2 kills standing in the same spot with a zoomed sniper rifle
Tidalis
Summer Swimming Hole - Create A Combo At Least 6 Deep
Metal Drift
Road Trip Rampage - Achieve 5 kills on each map
The Wonderful End of the World
Wonderful Big Bladder - Reset the game, and complete the entire thing in one sitting
Poker Night at the Inventory
Summer of 69 - Win a hand with a 6 card and a 9 card of any suit
Fate of the World
Catch Some Rays - Hooked up space solar power arrays by 2110
Movie Night - Download and watch a trailer in Steam
Killing Floor
Left 4 Dead Franchise
Batman: Arkham Asylum: Game of the Year
Sims 3 Franchise
Gothic Franchise
Far Cry Franchise
King's Bounty Franchise
Lost Planet 2
ProtoType
GTA 4 Complete
Atom Zombie Smasher
Jamestown
activities
Killing Floor
The Big Hunt - Kill a circus Scrake with a crossbow
Atom Zombie Smasher
Dog Days - Rescue at least 100 people in July
Left 4 Dead 2
Stream Crosser - Survive the Cold Stream campaign on any difficulty
RUSH
Solar Flare - Complete the Solar Flare level
Spiral Knights
Star-Spangled Bomber - Get Cracking! Add the Firecracker bomb to your arsenal
Guardians of Graxia
Fire Sale - Hit at least three enemy units simultaneously using either the Hell Storm or Wild Fire spell cards.
BIT.TRIP RUNNER
Roastin' yer Marshmallows - Bump into a fire in a Bonus Challenge
Show time - Post your own video in Steam
Monday Night Combat
Civ V Franchise
NFS Shift 2 Unleashed
King Arthur Franchise
Secret of Monkey Island Bundle
Stalker Franchise
Call of Duty 4: Modern Warfare
Deus Ex 1 GOTY and Deus Ex Invisible War
Wings of Prey
Guild Wars: Complete
Beat Hazard
AI War
activities
AI War: Fleet Command
Heat Wave Brown out - Accumulate a net energy balance of 300,000.
Monday Night Combat
Bayheimer - Cool guys don't look at explosions: This achievement can be earned by killing an enemy pro with explosion damage with your back turned.
Beat Hazard
Striptease - Strip the turrets off 2 bosses and keep them alive for 60s
Foreign Legion: Buckets of Blood
Chicken BBQ - Kill 25 chickens
Nation Red
Molotov Grill - Start a game in Strategic Mode and pick only four perks: Fire Starter, Friendly Fire, Remote Detonator and Molotov, then detonate 12 Molotov grenades in one game
And Yet It Moves
Bat-Wetter - Heat wave in the cave! Cool down a sweating bat with a drop of water in The Great Escape
Play time - Play a free game demo
Homefront
Fallout New Vegas Franchise
Mount & Blade Franchise
Serious Sam HD
Doom Complete Pack
RUSE and DLC
Bionic Commando
Bionic Commando Rearmed
Alpha Protocol
Singularity
Bully: Scholarship Edition
Frozen Synapse
Trine
activities
Mount & Blade: Warband
Lady Of The Lake - Give a male companion character a great sword
1... 2... 3... KICK IT! (Drop That Beat Like an Ugly Baby)
I Beat City 15 - Get 75%+ of the maximum score AND 50,000+ points with any song on City 15 replaced with zombie driverZombie Driver
Summer Hot Dog - Make a barbecue of 20 zombie dogs in a single slaughter mode match
Fortix 2
Harvester - Collect 50 sunflowers on Greemland or Classic levels
Homefront
Freedom - Complete chapter 2 in the Single Player Campaign
Trine
Summer Dip - Stay Underwater for 20 sec without taking damage
Serious Sam HD: The First Encounter
Swimming instructor - Drown an enemy
Say Cheese - Post a screenshot
Assassin's Creed franchise
Dragon Age franchise
Two Worlds II
Men of War: Assault Squad
Arma II Franchise
Kane & Lynch franchise
Call of Duty: Modern Warfare 2 series
Transformers: War for Cybertron
Sniper: Ghost Warrior
Tropico 3 Gold
Defense Grid
Torchlight
activities
Defense Grid: The Awakening
Out of Bullets - Beat all 5 'Out of Bullets' challenge modes without using Gun or Cannon towers
Men of War: Assault Squad
Grand Master of Barbecue - Complete the steam summer sale bonus mission!
Flight Control HD
Nice Shades - Open all umbrellas simultaneously on the Stunt airfield
The Polynomial - Space of the music
Sunburn - Use the sun to kill an enemy
A.R.E.S.: Extinction Agenda
It's Getting too hot - Trick a Bomber to hit and destroy a Zytron Walker (LA)
Iron Grip: Warlord
Everything Under the Sun - Purchase every available weapon and upgrade.
Write home - Recommend a game to your friends
games on sale
Plants vs Zombies
Magicka
Fable III and DLCs
Battlefield Bad Company 2
Bioshock Franchise
Darksiders
Resident Evil 5
Football Manager 2011
Aliens vs. Predator and DLCs
Half Life Franchise
Super Meat Boy
HOARD
activities
Magicka
Swedish Summer - Experience Rain and/or Blizzard 20 times during one Versus match to unlock a much needed treat
HOARD
Fireth of July - Cause 20 groups of fireworks to go off in a Hoard Mode level
Jolly Rover
Bon Voyage - Send a shipmate on a trip to remember
Super Meat Boy
Medium Rare - Spend as little time in hell as possible
Garshasp: The Monster Slayer
Cool'em in Summer - Throw ten enemies in the water while on the raft.
Introduce yourself - Post a comment on a friend's Steam Community profile page
Spiral Knights
Star-Spangled Bomber - Get Cracking! Add the Firecracker bomb to your arsenal
games on sale
SHOGUN 2
Call of Duty: Black Ops
GTA Classics
Star Wars: (KOTOR, Force Unleashed 2, Battlefront II, Empire at War)
The Heroes Pack
Dungeons
Devil May Cry 4
Just Cause 1 & 2
Railworks
Braid
SpaceChem
Hamilton's Great Adventure
activities
Hamilton's Great Adventure
Beach 2011 - Complete the "Up, up and away" extra level in the Amazon Jungle
SpaceChem
Science is an Indoor Activity - Beat 3 published ResearchNet assignments
Total War: SHOGUN 2
Summer Son - Your daimyo wins 3 consecutive land battles during the summer season
Alien Breed: Impact
Time to Party! - Complete 3 Co-op Assault multi-player games
Team Fortress 2
Escape the Heat - Jump into a pool of refreshing water while on fire
Dwarfs!?
Sharpshooter - Score 2500 in the Carnival minigame
Find your friends - Link your Facebook Profile in Steam
games on sale
Back to the Future
Dawn of War II: Retribution
The Witcher 2
Test Drive Unlimited 2
Operation Flashpoint: Red River
Medal of Honor
Borderlands Franchise
Elder Scrolls Oblivion GOTY
Lead & Gold
Blood Bowl: Legendary Edition
BIT.TRIP Franchise
Recettear: An Item Shop's Tale
activities
BIT.TRIP BEAT
Sunbathing - Be perfect in Transition up to the first intermission
Warhammer 40,000: Dawn of War II: Retribution
Promethium Summer - Kill 50 enemies while using a flamer
Lead and Gold: Gangs of the Wild West
Summer Hits - Kill 7 enemies in a row with headshots without dying
AaAaAA!!! - A Reckless Disregard for Gravity
Air. Wind. Sun. Pain. I Am All of This, and Your Mom Makes a Fine Pasta Dinner - Complete the Summer Sun level from the main menu with full points
Toki Tori
Get a Tan - Stand in all sun beams
Swords and Soldiers HD
Vamos a la playa - Complete Viking Campaign level 3 by killing all units.
Welcome to Camp - Join The
Summer Camp Official Group 
