Magic Forums

Hey guys accidentally posted this in wrong forum at first,, writing a book and need some information of onmyouji. How did people become onmyouji? What type of magic did onmyouji use? How did they specifically incorporate ying yang and the five elements into their magic? Furthermore does anybody have an specific example of types of spells they'd use and any examples of how they'd summon spirits such as foxes shikigami or shinigami? Thanks!