These are character sketches only -- the core of ideas.
Mike, I have a more detailed concept for the magus in mind, but I need to discuss it with you directly. (Yes, I'm going to play another Character With A Secret.)
Here ya go.
-----
THE MAGUS
He called himself Caine. By what arts he found the Covenant, none know but himself. He would give neither full name nor origin, saying that his magic spoke for itself, and he would swear what oaths were required of him.
Habitually hooded, favoring garments of deepest blue, he speaks little, preferring to closet himself in study. He seems knowledgeable about a great many things; his Latin is precise, his diction educated. Though he seems young, he commands a level of magic that few of his apparent age could rival; it is rumored that he dabbles in the darker arts. He is a newcomer to the Covenant, but he serves without hesitation.
He is of slightly above average height, slender in the manner of one who spends too little time outdoors, with a fair complexion, blond hair clipped short, almost tonsured, and vividly blue eyes. He plays the flute, and seems to prefer its companionship to that of the other magi of the Covenant.
THE COMPANIONS
Andras the Clockmaker. He comes from Geneva, or so he claims. His skill with things mechanical is something to marvel at. Unfortunately, his experiments extended to various devices that the religious authorities found to be "tools of the devil". Excommunicated and cast out of his native city, he sought refuge elsewhere, and eventually found the Covenant. Now he makes devices to order, for the magi. He is a bitter man, not quite thirty years old. He hates the Church and everything associated with it, and he wants revenge.
Tor. Once a knight, first-born son of a wealthy baron, he lost his inheritance when barbarians razed his father's manor and its surrounding lands. This by itself would have proved less of a disaster, had he not fled the battle, rather than fighting and dying by his father's side. He is not a man well-suited to fighting; though his natural talents are considerable, and his skills long-practiced, the sight of blood makes him nauseous and he is terrified of death. He also has a taste for luxury, and a tendency towards laziness. He does what he must for the Covenant, attempting to redeem some small measure of his honor. He can seem to be fervently religious, though cynics question the authenticity of his faith.