Black Death

(3/Day) After 4 consecutive hits, Shadow-like radiance descends on a creature you can see within a range of 15 ft. The target must succeed on a Dexterity saving throw or take 1d8 necrotic damage and 1d4 piercing damage. The target gains no benefit from cover for this saving throw.

The spell's damage increases by 1d8 and 1d4 with each consecutive hit.