What Does This Button Do??
Complete Arcade Ladder without blocking (allowed to continue)
4/23/2011
1:07:17 AM
Rare 10.7%
Final Transmission
Find the hidden signal in one of the Rat Man's dens
4/22/2011
8:51:00 PM
Very Rare 7.7%
Narbacular Drop
Place a portal under your co-op partner while they are gesturing
4/22/2011
5:54:34 AM
Very Rare 5.5%
Can't Touch This
Dance in front of a turret blocked by a hard light bridge in co-op
4/22/2011
5:36:09 AM
Very Rare 7.9%
Asking for Trouble
Taunt GLaDOS in front of a camera in each of the five co-op courses
4/20/2011
7:28:45 PM
Very Rare 6.0%
Obstacle Building
Complete all test chambers in the Excursion Funnels co-op course
4/20/2011
6:18:28 PM
Rare 15.7%
Bridge Building
Complete all test chambers in the Hard-Light Surfaces co-op course
4/20/2011
5:05:32 PM
Rare 20.6%
Confidence Building
Complete all test chambers in the Mass and Velocity co-op course
4/20/2011
4:28:40 AM
Rare 31.6%
Team Building
Complete all test chambers in the Team Building co-op course
4/20/2011
3:24:17 AM
Rare 46.8%