Brood of Hadar

You call upon Hadar the Ebon Hunger. Your foe screams, clutches its head, and falls. The target must succeed on a Constitution save against your spell save DC or take 3D10 necrotic damage. If the target is reduced to 0 hit points from damage caused by this spell, flying, fluttering, fanged shadows pour from your foe's open eyes, mouth and ears, and descend upon your foe's allies. Choose a new target within 15’ of your original target. The new target must succeed on a Constitution save against your spell save DC, or suffer 2D10 necrotic damage.

When cast with a higher level spell slot, the damage increases by 1D10 each for each spell slot above 4th spent to cast this spell.