Dark Bolt

You create an immaterial mass of cold enveloping darkness that lances out toward a creature within range. On a hit, the target takes 1d10 force damage and must make a Constitution saving throw. On a failed save, the target takes an additional 1d8 necrotic damage.

At Higher Levels. When you cast this spell using a spell slot of 2nd or higher, the damage caused by a failed Constitution saving throw increases by 1d8 necrotic damage for each slot level above 1st.