Hidden Truth Truth Series, Book 2.

Alissa never believed in magic. But then she went to the Hold, a legendary fortress where human Keepers once learned magic from enigmatic Masters. Under the tutelage of the last surviving Master, Alissa discovered that she had inherited her father's magical ability. But the Hold is ruled by Bailic, the renegade Keeper who seized the First Truth, a book of magic he will use to harness the might of the city of the dead and wreak a war of total deva...