Lady of the Moon by Mary Gillgannon
Approx. 53,590 words.
Published on August 24, 2012.
As the Romans threaten Britain, Sirona, a young Drui in training, seeks to use her visions to change the course of history. Aiding her are her fellow students, Bryn, who loves Sirona and wants to be a warrior rather than a Drui, and Cruthin, who is obsessed with seeking out the mysteries of the Otherworld.