Highlight the "System Configuration" option on the select screen. Hold R and press B. When the system config screen appears, press L + R on controller two. A sound will confirm correct code entry. A special environment options screen will appear. Increase the number of ships from three to five and credits from four to nine. Hold A + B + X + Y (in that order) on controller two. A sound will confirm correct code entry. A level select option will appear.
Press Start + Select on controller two. A sound will confirm correct code entry. The number of ships may now be increased to thirty and credits may be increased to ninety-nine. Any of the eight missions may also be selected for game play.