There are two kinds of werewolves in the Shine Cycle. Each kind is the result of arguably unwise experimentation in applied metaphysics, and a cautionary tale of “be careful what you ask for, because you just might get it.”
The first kind of werewolves came into existence a long, long time ago, when some wizards or sorcerers experimented with wolves and human nature, perhaps trying to absorb the lupine spirit and nature like the shamans in The Hallowed Hunt, or gain the ability to change their shape at will like animagi in the Harry Potter series.
Instead of whatever advantage they were trying to gain, these unwise dabblers became the changed beings we sort-of know from legend, with extremely fast healing but an extreme sensitivity (bordering on anaphylaxis) to silver, a similarly uncomfortable but less fatal reaction to salt water, and a sensitivity (positive or negative based on their spiritual state) to holy things and places, who change (usually monthly, unless they are more or less “right with God” and on consecrated ground) into the lupine form. And in that form, their will has been weakened by the pain of the transformation, and they are bombarded by extreme temptation to act like feral and perhaps rabid wolves.
Some werewolves of this kind, by stronger will or the grace of God, overcame these temptations, and for them the curse transmuted, so that they transform at will instead of monthly, or so that the animal instincts are closer to domesticated-canine than feral-lupine, and are weaker besides.
In addition to a general tendency toward weakened will and the temptations of the animal nature, werewolves tend to be what mages call “malleable,” that is, having a particular susceptibility to the effects of workings of applied metaphysics. They also tend to be more easily affected by mood- and mind-altering drugs when in their human mind and shape, though mind-altering substances usually lead to the lupine instincts taking over instead of having the effects they would on a normal human being. In the animal shape, such drugs are if anything less effective, and a werewolf’s body “burns through” them far more quickly, though the susceptibility to metaphysical effects remains the same in either shape.
These werewolves have always been somewhat rare, as the curse is only transmitted sometimes (like an infection) by fluids from the transformed state, and known werewolves have usually been hunted down (which explains why we don’t see them today, if our world is indeed the “our world” in which part of the Shine Cycle will eventually be set). But they did spread beyond our world (as the Shine Cycle conceives it), as the occasional werewolf stumbled—or, in a more sinister fashion, was summoned—through the portals between worlds that are scattered around (again, less commonly now).
So far I’ve only been talking about werewolves; the experiments have occasionally been repeated (with much the same results) with other animals, such as cats or even rats. Experiments with non-mammals tend to be almost invariably fatal, and the success rate (“success” here meaning “the subject survives”) with animals too different in body size from the subject is low but not quite that low—which explains why wolves are the most common in myth.
As I mentioned above, this curse—whose technical name is lycanthropy (for wolves) or more generally therianthropy—is sometimes overcome. For those rare individuals, it becomes a gift from God, used in his service (often to oppose a plague of “wild” lycanthropes terrorizing an area) for his glory.
The second kind of werewolves … have not yet come into being. They come into the Shine Cycle in the Game of Life sub-series, which is set in our own world’s future. They are the product of genetic engineering and a little applied metaphysics, by which scientists sought to replicate the beast of legend. And they very nearly succeeded.
These scientists and fumblingly-self-taught mages, working entirely with biological rather than spiritual material, created “binucleic man” (which may well be doubletalk up there with Lewis’s “less observed properties of solar radiation” in Out of the Silent Planet), able to (with training) shift form nearly at will, and with the same advantages as the “natural” lycanthrope, but subject to most of the same weaknesses (made far, far worse—the allergy to silver now reacts to alloys a natural werewolf would find innocuous, and the discomfort about salt water now objects to salted ground or a salt desert) but without the reactions to holy things or places or the particular severity of the mental effects.
This research was apparently done purely for “scientific” reasons, because someone thought it might be possible and looked “interesting” and might give results useful in developing a better theoretical understanding, rather than to create super-soldiers or something like that. But the trouble comes when this research is stolen by an invader from another world . . . but that’s another story, which I will tell in the first book of the Game of Life sub-series, The Invasion.