The Horse King (Dragonrealm)

Freed of the rule of the Dragon Kings, Lanith, warlord of Zuu, has launched a mad war of conquest. Cabe Bedlam and his friends prepare to join battle against him, only too late discovering that their true foe is a creature from beyond, a sadistic manipulator who desires to see the entire realm torn asunder. When Cabe's son, Aurim, becomes the monster's most powerful slave, it seems that there is no hope...unless the shadowy Darkhorse can overcome his fear and join forces with an enigmatic sorceress whose very existence should not be.