Six credits
Hold Select and press I, II, II, I three times, II four times. The word "CREDIT6" will blink above the title to confirm correct code entry.
Expert mode
Hold Select and press I, I, II, II.
Yellow mode
Hold Select and press I three times, II three times, I three times, II four times.
Blue mode
Hold Select and press I four times, II four times, I four times, II four times.
Green mode
Hold Select and press I three times, II three times, I four times, II four times.
Usagi 5 mode
Hold Select and press I five times, II, I five times, II, I five times, II.
Shield 5 mode
Hold Select and press I nine times, II eight times, I seven times, II six times, I five times, II four times, I three times, II, II, I.
Shield 4 more
Hold Select and press I four times, II three times, I, I, II.
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