Bloodstone

Fifteen years have passed since Darak’s quest. His son is now apprenticed to the village’s Tree-Father. Keirith unwittingly commits sacrilege by using his gift to commune with other creatures, the crime for which the evil shaman Morgath was destroyed. But a more immediate danger threatens the people of the Oak and Holly: the burgeoning power of the ancient enemy who drove them from their ancestral lands.
When Keirith is kidnapped, Darak sets off in pursuit. Their paths take them to the heart of a distant city where both father and son must confront their darkest fears in order to survive.