Vampiric Rend

As a vampire, you may cast a spell whilst making a melee attack against one creature within 5 feet of you. On a hit, the target suffers the melee attack's normal effects in addition to 1d8 necrotic damage. The necrotic damage dealt by the attack heals the vampire for the same amount. 

This spell’s damage increases when you reach certain levels. At 5th level, the melee attack deals an extra 1d8 (for a total of 2d8) necrotic damage to the target on a hit. Both damage rolls increase by 1d8 at 11th level (3d8) and again at 17th level (4d8).