Resplendent Refraction

The target’s skin becomes reflective and faceted like a finely cut gemstone. Until the spell ends, the target can use their action to fire a beam of reflected light in a 30-foot line. Each creature in that area must make a Constitution saving throw , taking an amount of damage determined by the light level around the target on a failed save, or half as much on a successful one.

In addition, whenever the target would take radiant damage (from a source other than this spell), it may instead reflect it as a reaction. If it does, it gains resistance to the triggering damage and may immediately fire a beam at the attacker as if it were in bright light.