Transfusion

You fingers become hollow talons that leech the blood from your enemies. Make a melee spell attack against a creature within your reach. On a hit, the target takes 2d8 necrotic damage, and you regain hit points equal to the amount of necrotic damage dealt. Until the spell ends, you can make the attack again on each of your turns as an action.

At Higher Levels. When you cast this spell using a spell slot of 4th level or higher, the damage is increased by 1d8 per level above 3rd the targeted creature gains 1 point of exhaustion on a failed CHA save equal to your spell save DC