Using Black Magic [Thaumotology/Horror]

[AlexanderHowl]

Black Magic (BM) is one of the key elements of a number of fantasy and/or horror settings, but I find that it is rarely done well. It generally ends up being campy or silly, with practitioners of BM generally failing spectacularly due to their own incompetence. In RPGs, it is usually so useless or so dangerous of a practice that few PCs will explore it, when folklore tends to suggest that BM should be useful and safe enough that anyone could use it to be a threat.

In GURPS, BM tends to either be Spiritual Assistance (see Thaumotology) or Corruption (see Horror). Spiritual Assistance basically means that a practitioner has an arrangement with a spiritual patron to provide magical energy in exchange for servitude (such as the classic 'deal with the devil'). Corruption basically means that a practitioner taps into a more impersonal force that slowly twists them into something fell (such as the Dark Side from the Star Wars Universe).

In my own modern horror settings, BM is as ubiquitous as it is secretive. The wealthy and powerful members of every society use BM to eliminate threats to the power and to protect their families from harm (or are puppets of those who use BM). Both forms of BM exist, with practitioners who share the same patron through Spiritual Assistance forming secret societies while practitioners who use Corruption are independent mavericks who buck the system. Since the magical system uses modified RPM rules, BM practitioners are quite powerful if they are willing to take risks.

If you use BM in your campaigns, how do you treat the subject? Which magical system do you have it modifying? Do you allow PCs to use BM or are practitioners of BM only NPCs?