The Shadow Riders / Seven Stars Assassins (セブンスターズ刺客, Sebunsutāzu Shikaku) are composed of seven duelists and their leader of varying origins and backgrounds who each have their own agendas.
The Shadow Riders are intent on resurrecting the Three Sacred Beasts (Phantom Demons in the Japanese version).
Several Duel Monster spirits not directly linked to the main cast appear throughout the series.
Several Pro League duelists are invited by Chancellor Sheppard to participate in the GX tournament.
The Group manufactured the ultimate D card Destiny End Dragoon for Aster, and when it was thought stolen his career was threatened.