Sharmat's Folly - The Slayer Series, #1

Trena Treelimb is a beautiful young Redwood Elf living in a time of peace in Wildingwood Forest, but she is about to become a woman, an adult, and that peace shall be disturbed. After Trena meets a strange man, she finds out that the life-giving Elder Tree has been poisoned. The Redwood Elves believe that this strange new bard can be none other than the hero of prophecy known as Slayer who possesses a special thing that they call Evilbane.
Thus the elves send Trena and the bard on a quest to destroy the source of the poison, which is the only way to save the Elder Tree and prevent the evil god and enemy of the Creator, wicked Samhain Sharmat, from escaping from his prison. This is Sharmat's Folly, Book One of The Slayer Series!