Saint Dragon (Commodore 64)

Cheat mode:
Press Fire at the title screen, then press P or Q five times during game play on level 1.

Cheat mode (alternate):
Load or reset the game, then execute the following BASIC commands before running or restarting the program.
POKE 8687,173

Unlimited lives:
Load or reset the game, then execute the following BASIC commands before running or restarting the program.
POKE 10469,173