Iron Grip
Never lose a cube in Chamber 6 of the Mass and Velocity co-op course
8/9/2012
5:15:58 PM
Ultra Rare 2.8%
Four Ring Circus
Enter 4 different portals without touching the ground in co-op
8/9/2012
4:12:09 PM
Ultra Rare 4.6%
Portal Conservation Society
Complete Chamber 3 in the Hard-Light Surfaces co-op course using only 5 total portal placements
8/9/2012
4:01:29 PM
Ultra Rare 2.1%
Empty Gesture
Drop your co-op partner in goo while they are gesturing by removing the bridge under them
8/8/2012
9:40:53 PM
Ultra Rare 3.9%
Narbacular Drop
Place a portal under your co-op partner while they are gesturing
8/8/2012
9:38:09 PM
Very Rare 5.5%
Can't Touch This
Take no damage from the final boss and clear the stage.
8/8/2012
3:37:26 PM
Ultra Rare 1.0%
Look Both Ways
Reach the goal in CRISIS CITY Act 2 without being hit by a tornado-carried cars or rocks.
8/7/2012
7:33:49 PM
Rare 11.8%
Walk on Water
Clear CHEMICAL PLANT Act 2 without entering the water.
8/7/2012
6:49:25 PM
Ultra Rare 1.4%
Color Power!
Get the Red Star Ring by using an Orange Wisp in PLANET WISP Act 2 and reach the goal.
8/7/2012
4:21:52 PM
Ultra Rare 2.0%
A Quick Breather
Get the Red Star Ring atop the highest spot in ROOFTOP RUN Act 2 and reach the goal.
8/7/2012
3:45:03 PM
Very Rare 7.1%
Secret Sleuth
Get the Red Star Ring located in the hidden room in SEASIDE HILL Act 1 and reach the goal.
8/7/2012
1:34:57 PM
Ultra Rare 2.3%
The Byway or the Highway
Get the Red Star Ring located on the shortcut route in SPEED HIGHWAY Act 2 and reach the goal.
8/7/2012
3:04:48 AM
Ultra Rare 3.2%
Jump for Joy!
Find the spring hidden in GREEN HILL Act 1 and reach the goal with a Red Star Ring.
8/7/2012
1:40:32 AM
Very Rare 5.6%
Bonds of Friendship
Complete all Challenge Acts featuring Sonic's friends.
8/6/2012
2:37:28 PM
Ultra Rare 2.5%