The Luminesti are a cult whose members have turned away from the The Church of Ezra and now worship the black moon Nuitari. They believe Ezra is a fraud and Sithicus is doomed. Their stated goal is to "ascend" to Nuitari.
Recently, the Luminesti killed Bishop Arel Caiven and took over the Cathedral of Ezra in Hroth.
The leader of the Luminesti in Hroth, Kharis Elnan, was defeated by the party while attempting to perform some kind of ritual of ascension. The party discovered a magical pearl which he had used to create the unnatural darkness around Hroth.