Vampiric Transference

You can siphon life force from others or yourself to heal wounds. You can choose to sacrifice some of your own health or make a ranged spell attack against a creature within 30ft. On a hit, the target takes 4d8 necrotic damage which can’t be reduced in any way, you channel this energy to mend another creature’s injuries, it regains hit points equal to the amount of necrotic damage dealt. 

At Higher Levels. When you cast this spell using a spell slot of 5th level or higher, the damage increases by 1d8 for each slot level above 4th.