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[edit] Super powered ship

To enable a super powered version of your ship, enter the following code. It will allow you to switch between the Rapid-Fire ability and the Super Laster ability by pressing

1. At the title screen, press × 10
2. On controller I, press and hold + + + . On controller II, press and hold +
3. Press on controller I. If successful, the title screen will blink back on to the screen.

Press to begin the game, and press to switch back and forth between the two weapons.

[edit] Increased Difficulty

To begin the game at a much higher level of difficulty, enter the following code. Because it involves the microphone, it is only possible to enter this code using a Famicom with a mic on the second controller. All of the enemies, as well as many of the tiles, will be altered in appearance, and many enemies will fire heat seeking fireballs.

1. At the title screen, press × 4
2. On controller I, press and hold + + + . On controller II, press and hold .
3. As you press on controller I, you must shout into the microphone on controller II. If successful, the title screen will blink back on to the screen.

Press to begin the game.