I am trying to remember a series of books, about three I believe, I read at least 20 years ago about a magic school / monastery.
A series of magical attacks take place, where the blame is placed on a Christ-like prophet, who has emerged from the desert and who in the end turns out to be genuine. The evil deity who is opposed to good is often described as "a diabolical machine" and when its plans are thwarted in the end, there is "gnashing of gears".
I recall one of the attacks being a homunculus, which when struck or destroyed shed it's armor revealing a smaller quicker homunculus which was even harder to destroy. Anyone able to help me identify this?