Stone Soldiers (Omnibus #1)

A collection of the first three books in the Stone Soldiers series:Mythical--two teens are drawn into a world of supernatural warfare when they stumble across the petrified body of Colonel Mark Kenslir in the Arizona desert. Kenslir returns to life but suffers from partial amnesia. With the help of the two teens, he sets out to recover his memories and complete his last mission--stop a prehistoric shapeshifter that steals the shaoe and memories of victims by tearing out and eating their hearts.
Brothers in Stone--Colonel Kenslir sets out to rebuild his team of super soldiers when reports arrive that a new shapeshifter is on the loose in America. But this shapeshifter is not alone. Now two prehistoric monsters are on the loose and decide to take the fight to the Colonel. Blood and Stone--the last shapeshifter attacks Alcatraz, stealing the hearts of the many paranormal beings imprisned there.
Fleeing to Mexico, it poses as the Mayan blood god Kukulcan and begins gathering followers and sacrifices. Colonel Kenslir and his team head south to stop the shapeshifter with an unlikely ally--Dr. Laura Olson, vampire, and the sole survivor of the Alcatraz slaughter.