Gryphon of the Hidden Realm

This is a long, classic fantasy book, in the tradition of Tolkien, CS Lewis and David Eddings, set in a different world.
Female gryphons are disappearing, abducted by the evil elves, the rulers of the Nomoi Empire. Hwedolyn must find out what is happening to them. He meets partisans, men, and must question ancient lore if he is to survive.
The story begins when a young orphan boy, a serving hand at the tavern high in the mountains, knows that every new moon, a barrel of mead is left out on th...