Abyssal Rebuke

Your gaze becomes venomous, as the creature that last damaged you is momentarily impaled by tendrils of crimson ichor. The creature must make a Dexterity saving throw. It takes 2d10 Piercing damage on a failed save, or half as much damage on a successful one. You heal for the same amount of damage dealt. 

At Higher Levels. When you cast this spell using a spell slot of 3rd level or higher, the damage increases by 1d10 for each slot level above 2nd.