Dark Nourishment

You attempt to rip out and absorb the life force of a creature within your reach.  Make a melee spell attack against the target.  On a hit, the target takes 6d8 necrotic damage, and you regain hit points equal to the amount of necrotic damage dealt. 

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d8 for each slot level above 3rd.