Kill 20 enemies in rapid succession

Complete all challenges in a single player mode

Resurrect an ally in coop mode

Complete all challenges in coop mode

Survive for 180 seconds

Kill 30 enemies with a single mega laser

Kill 1000 UFOs

Kill an enemy with a deflected bullet

Reach 1000 points without moving

Detonate 30 bombs with a single shot

Kill 1000 asteroids

Reach 2000 points in arcade mode

Reach 4000 points in arcade mode

Reach 6000 points in arcade mode

Reach 500 points without missing a single shot.

Have 50 asteroids in the level at the same time