Phantasm Calculus

The Phantasm Calculus (幻結石,) or Illusion Calculus, is a calculus the produces illusions.

Appearance
Unlike the Life and Nullstone, the phantasm calculus is shaped as two straight bones joined unevenly parallel together.

Background
Long time ago, a kemono has filled the stone with power and transformed it into a mountain to watch everything on its sight. It has been handed down in Yashima since ancient times.

Powers

 * Illusion: It allows Yashima to be invisible to the outside world and unrecognizable to them.