30 Lives
Press Up(2), Down(2), Left, Right, Left, Right, B, A at the title screen.
Achievements
Complete the following achievements to unlock Xbox Live Gamerscore points:
Armory (10 points): Collect gout different weapon power-ups.
Bulletproof (25 points): Complete the game in Arcade mode using only 1 credit.
Full Assault (30 points): Complete the game in under twelve minutes.
Infiltration (15 points): Destroy the alien tower at the end of the water level.
Partnership (20 points): Complete the game in Xbox Live Co-op mode.
Proficient (20 points): Complete the second tunnel with a score of 100,000 or more in Arcade mode.
Team Work (10 points): Score 100,000 points in an Xbox Live Co-op game.
Tunnel runner 1 (10 points): Beat the first timed tunnel with 33 seconds or more left.
Tough Guy (20 points): Get to the second tunnel without obtaining a single weapon upgrade.
Tunnel runner 2 (15 points): Beat the second timed tunnel with 55 seconds or more left.
Untouchable (10 points): Get to the first tunnel without losing a life.
Well Equipped (15 points): Collect three different weapons in the second tunnel.
Easy "Tunnel Runner" achievements
Get to the last station before the end and wait for time to run out. You will die and the clock will reset. You can now easily make the time requirement.