The Witch's Daughter — R.A. Salvatore

THE SPELL OF PEACE SHATTERED...

It had been twenty years since the Emerald Witch and the White and Silver Mages had prevailed against the devastating enchantments conjured up by the Black Warlock in his terrifying war of annihilation. His monstrous army overthrown, his spells cast down, and his spirit forced into the body of another, the warlock had taken two harrowing decades to win his war. But now he was ready to seek vengeance on witches and wizards, on humans and elves, as he sent out the call to marshal the greatest battalion of evil that had ever wreaked destruction. Yet even the Black Warlock could not foresee that a fifth power of magic was awakening in the mortal lands-- the witch's daughter, Rhiannon, heir to all the spells, both dark and light, of the earth itself....