Invincibility: Press Select to change the difficulty level
to #2 at the title screen. Begin game play, beat the high score,
get a game over then enter NUKENIN? At the high score screen.
Press Start to return to the title screen. Change difficulty
settings. Note: If you want to keep the same difficulty, press
Select cycle to it again. Begin, then pause game play.
Press Up/Left + Select + B on controller
two and Down/Right + Select + B on controller
one simutaneously.
