Wake Up Call
Survive the manual override
74.6%
You Monster
Reunite with GLaDOS
70.1%
Undiscouraged
Complete the first Thermal Discouragement Beam test
69.1%
Bridge Over Troubling Water
Complete the first Hard Light Bridge test
63.2%
SaBOTour
Make a break for it
58.1%
Stalemate Associate
Press the button!
57.3%
Vertically Unchallenged
Master the Repulsion Gel
55.1%
Tater Tote
Carry science forward
53.3%
Stranger Than Friction
Master the Propulsion Gel
51.9%
White Out
Complete the first Conversion Gel test
50.7%
Dual Pit Experiment
Do the same test twice
49.5%
High Five
Celebrate your cooperative calibration success
48.4%
Tunnel of Funnel
Master the Excursion Funnel
47.3%
The Part Where He Kills You
This is that part
46.5%
Lunacy
That just happened
46.1%
Scanned Alone
Stand in a defective turret detector
44.1%
Team Building
Complete all test chambers in the Team Building co-op course
40.4%
No Hard Feelings
Save a turret from redemption
35.6%
Good Listener
Take GLaDOS' escape advice
35.3%
Confidence Building
Complete all test chambers in the Mass and Velocity co-op course
33.6%
Drop Box
Place a cube on a button without touching the cube
32.4%
Preservation of Mass
Break the rules in Test Chamber 07
30.6%
Air Show
Perform 2 aerial gestures before touching the ground in co-op
28.5%
Bridge Building
Complete all test chambers in the Hard-Light Surfaces co-op course
26.9%
Gesticul-8
Perform all 8 gestures of your own volition in co-op
23.7%
Obstacle Building
Complete all test chambers in the Excursion Funnels co-op course
22.6%
You Saved Science
Complete all test chambers in all courses of co-op
18.5%
Portrait of a Lady
Find a hidden portrait
16.8%
Ship Overboard
Discover the missing experiment
14.5%
Can't Touch This
Dance in front of a turret blocked by a hard light bridge in co-op
12.0%
Pturretdactyl
Use an Aerial Faith Plate to launch a turret
11.4%
Rock Portal Scissors
Win 3 co-op games of rock-paper-scissors in a row
10.8%
You Made Your Point
Refuse to solve the first test in Chapter 8
10.6%
Door Prize
Examine all the vitrified test chamber doors
10.2%
Pit Boss
Show that pit who's boss
10.0%
Asking for Trouble
Taunt GLaDOS in front of a camera in each of the five co-op courses
9.8%
Final Transmission
Find the hidden signal in one of the Rat Man's dens
7.9%
Schrodinger's Catch
Catch a blue-painted box before it touches the ground
7.9%
Narbacular Drop
Place a portal under your co-op partner while they are gesturing
7.3%
Four Ring Circus
Enter 4 different portals without touching the ground in co-op
5.8%
Empty Gesture
Drop your co-op partner in goo while they are gesturing by removing the bridge under them
5.5%
Overclocker
Complete Test Chamber 10 in 70 seconds
5.1%
Smash TV
Break 11 test chamber monitors
4.1%
Party of Three
Find the hidden companion cube in co-op test chamber
4.0%
Professor Portal
After completing co-op, complete Calibration Course online with a friend who hasn’t played before
3.9%
Iron Grip
Never lose a cube in Chamber 6 of the Mass and Velocity co-op course
3.6%
Friends List With Benefits
While playing co-op, hug 3 different people on your friends list
2.7%
Triple Crown
Solve 3 co-op chambers in the Mass and Velocity course in under 60 seconds each
2.5%
Portal Conservation Society
Complete Chamber 3 in the Hard-Light Surfaces co-op course using only 5 total portal placements
2.5%
Still Alive
Complete Course 4 with neither you nor your co-op partner dying
1.7%
Talent Show
Never lose a cube in Chamber 6 of the Mobility Gels co-op course
1.5%