black magic

noun

1. Magic derived from evil forces, as distinct from good or benign forces; or magic performed with the intention of doing harm.

   “Witches are often accused of the same sort of Devil worship as the Black Magic followers.”

2. A technology, process, etc., that is mysterious, esoteric; anything which appears to be almost magic to those who do not understand it.

   “This is the fact of a new and vitally interesting experiment in the realm of physics, psychology, and art. There is no trick to this, as tricks go, except the mathematical magic of simple physics. Of course, simple physics for one man is black magic for another.”

   “The NCFLI will provide a step-by-step explanation of the processes involved. This should be done in order to dispel, to the extent possible, the notion that computerized production of legal texts and reports is "black magic," or that a hard copy of the processed text is something quite mysterious.”