Altered Beast

Level select:
Hold Down and press Reset at the title screen. The text "Free Play" will appear at the title screen to confirm correct code entry. Press Select equal to the number of the starting level you wish to begin at, minus one.

Alternately, after losing your lives, press Select at the "Continue" screen. You can now choose a level by repeatedly pressing Select. Press Start to resume game play at that level.

Sound test:
Hold Down and press Reset at the title screen. The text "Free Play" will appear at the title screen to confirm correct code entry. Then, hold Up and press Start.

Hard mode:
Intentionally lose the game. After the credits end, wait 30 seconds at the "Asmik" logo screen, then press Start.