Mecha Godzilla
Press [L], [R], [Y], [X], [A],
[B] at the title screen.
Spacecraft
Hold [L] + [R] and press [Up], [Left],
[Right], [Down], [Y], [X], [B], [A]
at the title screen.
Hints
Start with Super Fireball
Hold [Y] when powering on the game. When you start,
you will get the Super Fireball. Note: This does not work for
certain game paks.