A wizard cannot do everything; a fact most magicians are reticent to admit,
let alone discuss with prospective clients. Still, the fact remains that
there are certain objects, and people, that are, for one reason or another,
completely immune to any direct magical spell. It is for this group of
beings that the magician learns the subtleties of using indirect spells.
It also does no harm, in dealing with these matters, to carry a large club
near your person at all times.
-- The Teachings of Ebenezum, Volume VIII