Brightening Law

All chosen creatures in range( you cast this upon yourself) make a Con save, taking 6d8 radiant damage (half on success).

Enemies that harmed you or allies since your last turn roll with disadvantage and the enemies cannot take reactions until the end of their next turn.

Fairy Mark Interaction:

Marked Enemy: Takes +2d8 radiant damage on a failed save.

Marked Ally: Immediately regains hit points equal to your Charisma modifier + half the damage dealt to the marked enemy.