Shadows — E.C. Blake

In Masks, Mara Holdfast's life changed forever. As the daughter of the Autarch's Master Maskmaker, she had a clearly defined future: a quiet, ordered life in the capital, making Masks with her father and doing work important to the ruling Autarch. But when her Mask, specially made by her own father, cracked and fell to pieces during her Masking ceremony, Mara was exiled from everything she once knew.

Now she has become part of an underground rebellion, rejecting the unjust rules of a Masked society. She must try to understand her unprecedented ability to use all types of magic -- and to tear magic from the living bodies of those around her. But Mara has yet to discover just how horrifying her power can be….