Worldwalker Series

Lily Proctor is a sickly teenage girl who is transported to an alternate universe where magic is favored over science. But she finds herself at odds with Lillian, her identical other self in this world, who is also the tyrannical ruler of New Salem. Discovering that she is a witch, with powers that make her stronger and more coveted than she ever thought she could be, Lily must use her newfound talents to help fight a war that is brewing between the inhabitants of this world, and Lillian.