The Wizard Heir by Cinda Williams Chima

I finished the second book in this series and enjoyed it more than the Warrior Heir. This book introduces and follows a new character, Seph. He is a wizard that is brought up by an Enchanter since he is told that his parents died when he was young. He knows this is a lie, and so has no idea who his parents really are. Being a lesser guild, (enchanters, seers, warriors, sorcerers), Seph's guardian does not teach Seph much about the wizarding world and so he cannot control his magical abilities when they occur causing him to kill one of his friends by a fire that he starts. Eventually Seph is sent to an all boys boarding school in the US and soon finds out that it is run by a very powerful and evil Wizard who links other wizard kids to him and controls them. Seph somehow manages to make it through a year there being tortured and barely surviving as the headmaster tries to force Seph to link with him. Seph is saved by his true guardian and ends up in Trinity (the guild sanctuary that was enacted in the previous book by Jack and Ellen. The headmaster and Alumni (the linked students) continue to try to get Seph throughout the book and eventually get a hold of him.