Cruel Ultimatum

Choose a creature that you see within range and make a ranged spell attack against that creature.  On a hit that creature looses spell slots or uses of innate magic of total level 2d6.  The creature takes 8d6 necrotic damage and you gain 3d6 hit points.

At higher levels: when you cast this spell using a spell slot of 7th or higher, the damage and hit points all increase by 1d6.