True Annihilation

You attempt to truly annihilate your opponent, wiping them from reality.

Choose a target within 120 feet of you. They must make a Constitution saving throw, taking 10d10 necrotic damage on a failed save, or half as much on a successful one. In addition, if this damage brings them to 0 hit points, they immediately die and cannot be resurrected by any means short of a wish spell.