Re: Black magic.
I did study Witchcraft, at college, around about 1970.
The tutor convinced me that a witch was someone who could exert huge power over others, usually starts as good but later becomes evil.
Each week I had to research a person (non of them religious) and come back to the tutorial with that - and any suggestion of an invention which made such convincing possible.
Boring i know. One example was Adolf shown as the Master at Nuremburg, in front of thousands of troops, remember the photo?
The invention was interesting as we decide it could have been the invention of the Loud Speaker, not long before, which enabled him to do the speech!!
Anyway - boring bit over.