The Druid of Shannara

The evil Shadowen still retain their hold and continue to drain the Four Lands of the magic that had been their lifeblood. The King of the Silver River, a fabulous being as old as mankind, creates a daughter named Quickening and sends her to assist. She joins Morgan Leah and Pe Ell, an assassin who plans to eventually kill her, on a journey to the far north to recover the lost magic, a process that involves the need to capture the Black Elfstone.