Nightseer

Keleios the Half-Elf was but five years old when she saw her mother murdered by the evil witch Harque. For years she has asked the gods for the strength she'll need to avenge this foul death, and it seems the gods have answered her. She's been granted an array of powers never before seen in one person, but she has also acquired a most terrifying burden, a demonmark. This mark can open the door to undreamed abilities, but it can also open her soul to the forbidden dark side of magic. Keleios must choose between the demonmark's tainted power and the lives of those she holds most dear. In an epic battle of good versus evil, of enchanted swords and shapeshifting dragons, of unquenchable hatred and unlikely love, Keleios must face her own demons—before she can acquire the most important power of all: the power to forgive.

Laurell K. Hamilton