Nine continues: Press X, A, L, R, Left,
then hold L and press X, C, Z, A,
Right(2) at the game start screen. A sound will confirm
correct code entry.
Additional difficulty levels: Hold X and press Z, C, L,
B, Left, R, L at the game start screen.
A sound will confirm correct code entry. Very easy and abnormal
difficulty levels will be selectable options.
Rapid autofire: Hold B and press Y, Right, Left,
X, Z, L, R at the game start screen.
The sound of an explosion will confirm correct code entry.
