51 Steam Achievements
Wake Up Call
Survive the manual override
You Monster
Reunite with GLaDOS
Undiscouraged
Complete the first Thermal Discouragement Beam test
Bridge Over Troubling Water
Complete the first Hard Light Bridge test
SaBOTour
Make a break for it
Stalemate Associate
Press the button!
Tater Tote
Carry science forward
Vertically Unchallenged
Master the Repulsion Gel
Stranger Than Friction
Master the Propulsion Gel
White Out
Complete the first Conversion Gel test
Tunnel of Funnel
Master the Excursion Funnel
Dual Pit Experiment
Do the same test twice
The Part Where He Kills You
This is that part
Lunacy
That just happened
Drop Box
Place a cube on a button without touching the cube
Overclocker
Complete Test Chamber 10 in 70 seconds
Pit Boss
Show that pit who's boss
Preservation of Mass
Break the rules in Test Chamber 07
Pturretdactyl
Use an Aerial Faith Plate to launch a turret
Final Transmission
Find the hidden signal in one of the Rat Man's dens
Good Listener
Take GLaDOS' escape advice
Scanned Alone
Stand in a defective turret detector
No Hard Feelings
Save a turret from redemption
Schrodinger's Catch
Catch a blue-painted box before it touches the ground
Ship Overboard
Discover the missing experiment
Door Prize
Examine all the vitrified test chamber doors
Portrait of a Lady
Find a hidden portrait
You Made Your Point
Refuse to solve the first test in Chapter 8
Smash TV
Break 11 test chamber monitors
High Five
Celebrate your cooperative calibration success
Team Building
Complete all test chambers in the Team Building co-op course
Confidence Building
Complete all test chambers in the Mass and Velocity co-op course
Bridge Building
Complete all test chambers in the Hard-Light Surfaces co-op course
Obstacle Building
Complete all test chambers in the Excursion Funnels co-op course
You Saved Science
Complete all test chambers in all courses of co-op
Iron Grip
Never lose a cube in Chamber 6 of the Mass and Velocity co-op course
Gesticul-8
Perform all 8 gestures of your own volition in co-op
Can't Touch This
Dance in front of a turret blocked by a hard light bridge in co-op
Empty Gesture
Drop your co-op partner in goo while they are gesturing by removing the bridge under them
Party of Three
Find the hidden companion cube in co-op test chamber
Narbacular Drop
Place a portal under your co-op partner while they are gesturing
Professor Portal
After completing co-op, complete Calibration Course online with a friend who hasn’t played before
Air Show
Perform 2 aerial gestures before touching the ground in co-op
Portal Conservation Society
Complete Chamber 3 in the Hard-Light Surfaces co-op course using only 5 total portal placements
Four Ring Circus
Enter 4 different portals without touching the ground in co-op
Triple Crown
Solve 3 co-op chambers in the Mass and Velocity course in under 60 seconds each
Still Alive
Complete Course 4 with neither you nor your co-op partner dying
Asking for Trouble
Taunt GLaDOS in front of a camera in each of the five co-op courses
Rock Portal Scissors
Win 3 co-op games of rock-paper-scissors in a row
Friends List With Benefits
While playing co-op, hug 3 different people on your friends list
Talent Show
Never lose a cube in Chamber 6 of the Mobility Gels co-op course
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