Cheat mode:
Press Start at the title screen. Highlight the "System Configuration" option, then hold R and press Start. Press L + R on controller two at the system configuration screen. The current stock, credits, and stage will appear. Hold A + B + X + Y (in that order) on controller two. 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.
Cheat mode (alternate):
Highlight the "System Configuration" option on the select screen. Hold R and press B. When the system configuration 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.
Bonus level:
Reach the water stage on level two. Fly across the water until reaching a yellow square marked with the letter "E". Steer your ship behind the square and press Up. If your ship was positioned correctly, it will warp to a bonus level.
