Exorcism

You ignite a creature with the purifying power of the light, searing it to the bone. The target must make a Constitution saving throw or take 8d8 holy damage, or half as much damage on a successful one. If the target is a fiend or undead creature, it has disadvantage on the saving throw and takes 8d12 holy damage, or half as much damage on a successful one, instead.

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 (or 1d12) for each slot level above 4th.