The Mistmantle Religion is akin to Methodist Christianity, and remains unnamed. It worships the Heart, which is served by Priests, who give blessings, perform weddings, ordain Kings and Queens, and perform naming ceremonies, and operate in other functions. It considers the Heartstone sacred. The Priest in service on Mistmantle is responsible for the protection of the Heartstone, which almost exclusively stays in their care, stored safely inside a ceremonial box.
As of Urchin and the Rage Tide, there are two known living Priests, and one Priest-in-training. Brother Flame acts as the Priest for Whitewings, and Brother Juniper is the Priest on Mistmantle, who is currently training Brother Tide to eventually take his place.