Unlimited ammunition:
Hold 1 + 3 + 5 + 7 + 8 + 9 at the control options screen. You will hear a sound if you have entered the code correctly.

Boss fights:
Start a new game and submit the code 1328 to start at Sector 2. Complete Sectors 2, 3, and 4. Then, submit the code 1008 to jump to Sector 1. After Sector 1 is completed, the Bosses from all four Sectors will have to be fought in order.

Fire Super Weapon during demo:
Press 1, 2, or 3 during demonstration mode