Cheat Codes:
X, SQUARE, TRIANGLE, X, CIRCLE - Infinite lives
SQUARE, TRIANGLE, X, TRIANGLE, CIRCLE - Rapid fire 
CIRCLE, TRIANGLE, TRIANGLE, SQUARE, X - Super shots 
CIRCLE, CIRCLE, X, TRIANGLE, SQUARE - Gun sights 
SQUARE, CIRCLE, X, TRIANGLE, CIRCLE - Sniper mode.