is this song unlockable ? i couldn't find it when i tried the game at a convention, is this a special song ? (i mean do you need a card or something ?)
Yes! KONAMI's E-amusment PASS is required to play this song. Also, this song is an extra stage only song, and you need to clear this song in the extra stage to unlock it. (This was a while ago, so the unlock conditions may have changed now.)