Oni Masks can each summon a different tribe of Shadowkhan once the mask is attached to a host's face, but if all nine masks are brought together in one location, the masks shattered into pieces and the Oni spirits are set free, summoning enough Shadowkhan to engulf the Earth in eternal darkness. Each mask has a different tribe of Shadowkhan and a different removal ingredient. The removal spell also requires a lizard tail, wolfsbane, sulfur root, and left eye of newt.