Books in the Shadow Barrier Trilogy series

No monster has ever set foot inside the stronghold of Amul Dun.Until now.A traitor hides within its walls with orders to destroy Katira, her father, and the world they have sacrificed so much to save.Wrothe is not as defeated as everyone believed. She plots her revenge even while banished to the other side of the shadow barrier.Amul Dun's only hope lies within a dying man's last words.Katira's only hope lies in mastering the power of the Khandashii. Without guidance, it will kill her. Her apprenticeship tests not only her strength and courage, but her determination to do what is necessary as well.If she fails to master her power she won't be able to protect the people she's come to love against Wrothe. She can't let that happen, not again.