On the listed stages, enter the secret commands to get the following effects.

Effect	Code
100 Missiles	Stage 3: Start and Speed Fast.
100 Missiles	Stage 9: Vulcan Cannon + Missile and Stick Right.
250,000,000 Points	Stage 21: Start + Vulcan Cannon + Missile + Foto Sensor and stick Up.
50,000,000 Points	Stage 11: Vulcan Cannon + Missile and Stick Left.
DUKE Message	Demo: Start + Vulcan Cannon + Missile + Foto Sensor and Stick Right.
Secret Message	Stage 5: Start + Vulcan Cannon + Missile.
Secret Message	Stage 13: Start + Vulcan Cannon + Missile and Stick Left.
Secret Message	Stage 16: Start and Stick Down.
Secret Message	Stage 19: Start.
Secret Message	Stage 1: Start + Vulcan Cannon + Missile.
Secret Message	Stage 23: Start + Vulcan Cannon + Missile + Foto Sensor.