ACHIEVEMENT - HOW TO UNLOCK
Armory (10 points) - Collect all different weapon power-ups.
Team Work (10 points) - Score 100,000 points in an Xbox Live Co-op game.
Untouchable (10 points) - Get to the first tunnel without losing a life.
Tunnel runner 1 (10 points) - Beat the first timed tunnel with 33 seconds or more left.
Infiltration (15 points) - Destroy the alien tower at the end of the water level.
Tunnel runner 2 (15 points) - Beat the second timed tunnel with 55 seconds or more left.
Well Equipped (15 points) - Collect three different weapons in the second tunnel.
Tough Guy (20 points) - Get to the second tunnel without obtaining a single weapon upgrade.
Proficient (20 points) - Beat the second tunnel with a score of 100,000 or more in Arcade mode.
Partnership (20 points) - Beat the game in Xbox Live Co-op mode.
Bulletproof (25 points) - Beat the game in Arcade mode using only 1 credit.
Full Assault (30 points) - Beat the game in under twelve minutes.