Dark Tendril of Hadar

You transform one of your hands into a black tentacle of Hadar, the Dark Hunger, lashing out at a creature within range. Make a ranged spell attack roll. On a hit, a creature suffers 1d6 necrotic damage. Half of the damage done is converted to a spectral shield that grants temp. hit points equal to half the damage done (minimum of 1 temp. hit point).  

At Higher Level. Increases the damage dice by 1d6 at 5th, 11th and 17th level.