16% · 6h played
Team Building
Complete all test chambers in the Team Building co-op course
High Five
Celebrate your cooperative calibration success
Preservation of Mass
Break the rules in Test Chamber 07
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
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
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