Call of the Abyssal Voice

You release a chilling call that reverberates with the power of the Abyss. All creatures within 30 feet of you must make a Charisma saving throw or become stunned for 1 minute. Additionally, creatures that fail the saving throw take 4d8 necrotic damage. Creatures that succeed on the save take half damage and are not stunned.

Using a Higher Level Spell Slot. The damage increases by 1d8 for each spell slot level above 1.