The Summoner by Gail Z. Martin

After his family is slaughtered in a brutal coup, a young prince with the rare power to command the dead flees his usurper brother and the dark sorcerer behind the throne. On a perilous journey to master his summoner magic, he gathers a band of allies—loyal friends, a hardened sellsword, a gifted healer—and forges uneasy pacts with vampires and shapeshifters. Haunted by restless spirits and guided by a sacred order, he races to thwart a plot to unleash an ancient evil while preparing to reclaim his kingdom.

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