Enter sound test option and play the following songs (in order): 7, 7, 7, 7, 9, 3, 10.
Fast mode
Enter sound test option and play the following songs (in order): 7, 5, 8, 4, 1, 10, 5, 1, 10, 5, 1, 8.
Maximum HP
Enter sound test option and play the following songs (in order): 3, 7, 3, 5, 1, 8, 2, 1, 9, 8, 4.
Nine credits
Enter sound test option and play the following songs (in order): 0, 3, 3, 8, 3, 9, 0, 0, 8, 0.
Slow mode
Enter sound test option and play the following songs (in order): 0, 0, 0, 0, 0.
Start at second half of game
Enter sound test option and play the following songs (in order): 1, 6, 0, 10, 5, 2, 10, 3, 8. Game play will begin after powering up with heavy artillery and speed.
Unlimited ammunition
Pause game play and press II, Left, II, Up, I, Right, I.
Unlimited bombs
Pause game play and press I, II, Left, I, II, Up, I, Down, I, II, Select, Up, Down.
Unlimited credits
Enter sound test option and play the following songs (in order): 3, 4, 3, 8, 0, 1, 4, 1, 14, 14.