Circle of Death (variant)

A sphere of negative energy ripples out in a 40-foot- radius sphere from a point within range. Each creature in that area must make a Constitution saving throw. A target takes 10d6 necrotic damage on a failed save, or half as much damage on a successful one.

At Higher Levels. When you cast this spell using a spell slot of 7th level or higher, the damage increases by 3d6 for each slot level above 6th.