The Raven Queen Book 3

Maddy and her cousins are ready for battle. War in the faerie realm threatens to spill into the human world. The three cousins are determined to protect all they love from the Tuatha, the fearsome faerie leaders. As the Morrighan, the supreme monarch of the Tuatha, awakes, Maddy realises she's going to need more than just physical strength and luck to survive. The Tuath are notorious tricksters, and Maddy will have to outsmart them for good - or else plunge two whole worlds into the darkest chaos.