Nualis is a world set squarely in the Medieval period. The largest geo-political entity is the Holy Mother Church. Magic use is known and understood here, although not accepted unless
a) one is a member of the cloth who has taken a special vow
or
b) tough enough that the Church can't do much about it.
The Church is known to be involved in the development of the magically gifted. It is an open secret that some of the cloistered orders are, in fact, training camps for the development of fanatically devoted battle choirs.
If the laity practice magic in public then they will be "interviewed" by the Holy Office and consigned to the flames for the purification of their soul. Savage, fulminating power is an acceptable remedy in law against the inevitability of this process.
The current pope is rumoured to be a skilled sorceror, and possibly the greatest arithmetician of the age. They say that he knows the secret of long division, and the viziers of the Orient are said to tremble at the mention of his name. There is a tale recounted in places no decent person would be seen that His Holiness has performed the operation of division by zero on a recalcitrant and unrepentant heretic.
The Comte de Versillac is an hideously powerful Gascon wizard and alchemist. Although neither undying or immortal, the Comte has remained alive for several centuries by means of the elixirs of youth that he prepares. He is not a priest. He maintains his continued liberty by slaying the crusades that come to take him. To the last man.
Amongst the magic which he regularly sustains about his person is a spell that detects and locates priests of the Holy Mother Church. This is not a targeting sense, although he can use it to follow someone until he can target them. He will do this, for he is filled with an endless hatred for the Church and would bring the institution down if he could.
The Church would dearly love to bring him to trial, where they could quickly find him guilty of almost anything they liked, so great is their reciprocal animosity. With some justification, however, for in a world where priests are rarely harmed physically, de Versillac offers no quarter.
The Eye of Discord is an arms dealer, operating out of a variety of ports. Intelligence from a variety of sources indicates that he is likely a member of the Church. The favoured conjecture at the moment is that he is a bishop without see because such a position provides mobility and authority to maintain his concerns.
Notably, there are two secret cults that pursue their own mysterious agenda, the Jasonites and the Medeanites. They are opposed to each other. One of these organisations, or both, have been responsible for the abduction of young village idiots in the past, to create something called the 'Whisperfall'. Wegin the Inscrutable opines that this 'Whisperfall' is a collection of idiot savants, connected together by relays of Mind Mages.