The mage wars : a Valdemar omnibus / Mercedes Lackey & Larry Dixon.

Black gryphon -- White gryphon -- Silver gryphon.

FANTASY. Set around three thousand years before the rest of the Valdemar series, this is the ancient history of Velgarth and the story of Skandranon Rashkae, a gryphon with gleaming ebony feathers, keen magesight and acute intelligence. He is the fulfillment of all that the Mage of Silence, the human sorcerer called Urtho, intended to achieve when he created these magical beings to be his champions, the defenders of his realm - a verdant plain long coveted by the evil mage Ma'ar. Together with Amberdrake, a Healer of body, mind and spirit, Skandranon will defend his nation from his evil counterparts created by Ma'ar, the makaar. The glorious city of White Gryphon will rise from the ashes, but it will take careful negotiation, spying and terrible war against the mysterious Black Kings to secure the stronghold. Even then, the elite guard force, the Silver Gryphons, will discover a greater terror lurking in the forests beyond the city walls...