Blood Lash

You pull blood into a whip-like weapon, make a melee spell attack roll against a creature within range, dealing 4d6 necrotic damage on a hit. You may empower this spell by sacrificing 1 of your hit dice, rolling it, and adding the result to the damage. The hit die is then expended as if it were used.

At Higher Levels. For every level above 2nd, add an additional 1d6 to the damage, you may also expend an additional hit dice for each level above 2nd that you cast this spell at.