If you take the ramblings of some old fool and bind them together, you may just find a gem of literature.Lore found here relates to literature from throughout Isekai.
As clear as day, the name of this book finds her, the Book of Exalted Deeds. A book that holds the truth of the Pantheons of Isekai and their secrets, but it also holds great power that can be bestowed upon those that are devout enough in their faith.
While some might call this a manual it is closer to a large philosophical and scientific thesis on the nature and classification of magic as a whole. This book takes great pain to explain and classify magic in general and by spell,