The Outstretched Shadow: 1 (The Obsidian Trilogy) - Tapa dura

Centuries after defeating a vast army of Demons with the help of their Elven allies, dragons, unicorns, trolls, and mages, the Demons once again threaten humankind, this time without their former alliance, unless the fugitive Kellen, his long-lost mage sister Idalia, an Elven warrior, a talking unicorn, and a Demon's child can overcome despair to save the Elven Country. 100,000 first printing.

The Books of Wild Magic

There were three of them, at the bottom of a pile of ledgers, very slender volumes bound in some fine-grained, dark leather, with just a touch of gilt on the spine. Kellen found himself turning them over in his hands with some puzzlement. There was nothing on the spine of each but a single image-a sun, a crescent moon, and a star. Nothing on the cover, not even a bit of tooling, and the covers themselves were in pristine condition.

Odd. Definitely out of keeping with the rest of the used bookseller's wares.

He opened the front covers. The title pages were handwritten, not printed. The Book of Sun. The Book of Moon. The Book of Stars. He leafed through the pages, trying to puzzle out the tiny writing. The contents were handwritten as well . . . and seemingly dealt with magic.

They shouldn't be here at all! Kellen thought with a sudden surge of glee. Books on magic were very closely kept, with Students returning their workbooks to their Tutors as they outgrew them. And these weren't any of the recognized Student books, or anything like them, as far as Kellen could tell.

Without bothering to look through them further, he put them on the top of his pile and caught the stallholder's eye.

"Got younger sibs at home, do you?" the man asked as he wrote up a bill of sale with the merest stub of a graphite rod.

"No," said Kellen, startled. "Why do you ask?"

"Well, children's stories.... The man gestured at the three books. He handed Kellen his receipt.
Kellen studied it in confusion. There were his Histories, but what was this? Tales of the Weald, Fables of Farm and Field, and Hearth-side Stories?

There was something very odd about those books.
--from The Outstretched Shadow