Ball of Degeneration

A pure black streak absorbs light from your pointing finger to a point you choose within range and then blossoms with a loud scream into an eruption of darkness. Each creature in a 10-foot-radius sphere centered on that point must make a Dexterity saving throw. A target takes 6d6 damage, 3d6 psychic and 3d6 necrotic and blinds them on a failed save, or half as much and not blind on a successful one

The darkness spreads around corners. As long as any part of a creature is inside this ball they must make the saving throw.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.