The Talismans of Shannara by Terry Brooks

Although some of the goals to keep Shannara safe had been met, the work of Walker Boh, Wren, and Par was not yet done. For The Shadowmen still swarmed over the Four Lands, poisoning all with their dark magic. Each Shannaran had a special death waiting for him- at the hands of The Shadowmen-unless Par could find a way to free them all with the Sword of Shannara.