Over millennia ago, an ancient clan known as the Ningen were faced with the task of protecting their race from the horrible creatures known as Oni. The Oni tribe that stood against the Ningen were dark shamans known as the Kurayami. For years, these opposing tribes fought for the rights to be the dominant creatures of the world – and to send what was left of the defeated tribe into the shadows forever. Twelve shamans from the Ningen tribe sealed the power of eleven Oni into masks that would grant them the power to fight the Oni, by using there own powers against them. The strongest warriors of the Ningen tribe used the masks to drive the Kurayami back into the shadows. However the battle cost the lives of ten of the warriors. The remaining warrior used the magic of the eleven masks to seal