Level select:
Hold X + Y + Z + L when the phrase "Internal memory will be used for autosave" message appears while the game loads. The message "Cheats enabled" will appear to confirm correct code entry. Press Up or Down when the name of the next city and day appears to select a new country. Press Left or Right at the same screen to select a city. Additionally, keep X + Y + Z + L held for a sound test option. Note: This must be done before the phrase "Now Loading" appears.

Alternate ending sequence:
Successfully complete the game. Hold A + B + C when the ending sequence begins and keep the buttons held until the credits appear.

Alternate colors:
Highlight George, Ralph, or Lizzy at the character selection screen. Press Up after selecting a character to choose a new color.

Restore energy:
Quickly press Start (15) when your monster is almost out of energy. Your energy will be restored after losing the current life.