Allowance

You force a creature to take on a part of your own bane, making it experience agony it's body is not used to. The target must succeed on a Charisma saving throw or take 1d8 Necrotic damage. If you are at half hit points or lower, the target instead takes 2d8 Necrotic damage.

The spell's damage increases by one (or two) die when you reach 5th level (2d8 or 4d8), 11th level (3d8 or 6d8) and 17th level, (4d8 or 8d8)