Black/Matrix AD Cheats (Dreamcast)

The "fake" method of unlocking Zero is to press X, Y, A, B, Start when the Japanese text
"Goshujin-sama wo erande kudasai" appears. Zero will show up to the right of Prague, but
only says "Gomen ne" when you try to select him.

  The real method: rotate the Analog-stick in two clockwise circles followed by Start when
the Japanese text "Goshujin-sama wo erande kudasai" appears. Zero will appear on the
character selection screen.