Bonuses:
During the first couple levels, anytime you see a crack in the wall, shoot it. The wall will break open and you will find extra lives, money, etc. hidden inside.
Cheat Codes:
Activate the following cheats in the indicated screen by entering the corresponding codes:
CHEAT FUNCTION – SCREEN – CHEAT CODE
Level skip – Game play – cheate
1000 HP – Game play – cheath
All weapons – Game play – cheatw
1,000 additional ammunition – Game play – cheata
50,000 additional money – Shop – cheatm
Night vision and flashlight mode – Game play – cheatf