Unlimited lives:
Type [Apostrophe] C [Apostrophe] at the high score screen.
Unlimited lives (alternate):
Load or reset the game, then execute the following BASIC commands before running or restarting the program.
POKE 11312,128
SYS 2560
Unlimited lives (alternate):
Load or reset the game, then execute the following BASIC commands before running or restarting the program.
POKE 11387,173
Invincibility:
Load or reset the game, then execute the following BASIC commands before running or restarting the program.
POKE 5346,173