Continue game play:
Hold Up + Select + I and press Run at the title screen. One continue will be available when game play begins.

Additional items:
Hold Up + Select + II and press Run at the title screen.

Alternate enemies:
Press Up, Down, Left, Right, I, II, Run at the title screen. Enemies will have the appearance of your character.

Monochrome mode:
Hold Up + I + II and press Run at the title screen.

Control demonstration mode:
Hold I during the demonstration sequence to keep the CPU from jumping. Hold II to keep the CPU from attacking.