Essence Shear

You lash out at a target within range, rending the very life essence! Make a ranged spell attack roll. On a hit, deal 3D8 Necrotic damage. The life essence is manifested into a life-shield, granting the caster Temp. Hit points equal to half the damage done.

This spell has no effect on mechanical creatures.  

At Higher Level. Increasing the damage dice by 1D8 for each spell slot used above 2nd level.