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.