Acceleration Celebration
Activate the Accelerator Suit three times in any mission
9/13/2009
2:58:28 AM
Common 55.3%
Double Barrel Roll
Perform 10 barrel rolls in unison in any level in co-op
9/11/2009
2:39:45 AM
Rare 20.2%
No "I" in Team
Complete mission with higher than 50% Dual Targeting kills
9/1/2009
2:18:46 PM
Rare 45.9%
Run-and-Gunner
Kill 20 enemies by shooting from the hip (without aiming with the L1 button)
7/21/2009
5:52:22 PM
Rare 22.5%