The domain of Selûne represented the goddess' will to protect the world from evil and her part in the endless war of light against darkness. As such, followers of Selûne that had a more aggressive stance and had the will to fight against evil with all their might, a point of view usually not associated with her, followed this specific aspect of the goddess.
Power of Selûne's domain
Any divine caster who worshiped Selûne, and followed this aspect of hers, gained resistance against necrotic and radiant damage. This blessing also protected the caster and their allies against their enemies' physical attacks, by creating temporary barriers of moonlight around them.