As has happened in several other cycles, the last time the comet came around, there was a disagreement on which prophet was the real one. A few priests rebelled and followed Ivo instead of the more popular Samuel. After Ivo was sacrificed, these priests started up a small, close-knit following which has become a cult that controls every aspect of its members’ lives. Ivo had asserted that the sacrifice of human lives was necessary to keep the Advocate’s attention on your community, and so this cult does abduct and sacrifice a number nonbelievers and mages in a yearly ritual. They also otherwise destroy livestock and goods in the name of the Advocate.
Since the leader is a Moonkin, they believe that the Moonkin are inherently wise and ought to be revered and raised for leadership.