Asmodean Rebuke

In response to taking damage, you speak the same cursed, black words the Lords of the Hells himself Asmodeus spat as he fell from divine grace, and the creature that dared to harm you is engulfed in the brimstone flames of the Nine Hells. The creature must make a Dexterity saving throw, and on a failed save it takes 4d10 fire damage and 4d10 necrotic damage, or half as much damage on a successful one. In addition, if the creature is a devil, on a failed save their immunity to fire damage is bypassed by the tortuous flames of their master.