Demon Soul

Demon Soul (鬼·ソウル Oni Sōru) is a Caster Type Magic and a form of Take Over. It is mainly used Caelum.

Description
This particular form of Take Over is strange in its own way being that it manifests from the user's subconsious thoughts and hidden desires. Usually, the outcome is in the form of an animal, such as Feza's humanoid raven appearance. 99.9% of people have an Demon Soul Take Over, with only 15% of them ever aweakning it in their lifetime. As this magic drains a large amount Eternano, only 3% will  survive after it's use. The 1% who are lucky have the ability to use this magic on several occasions. Additionally, because of the heavy strain, the user can be commatised, lose their ability to use Eternano, or face eternal slumber.