You call down an explosion of radiant fire from the heavens on a point you can see in range. Each creature in a 15-foot-radius sphere centered on that point must make a Constitution saving throw. On a failed save, a creature takes 6d6 radiant damage and is marked with holy radiance until the end of your next turn. On a successful save, a creature takes half the damage and isn’t marked. The next attack roll against a marked creature before the end of your next turn has advantage.