Essence Drain

You extend necromantic energy outwards that takes the shape of shadowy claws that attempt to siphon life from a target creature within range. The target must make a Constitution saving throw. A creature has disadvantage on this saving throw if its current hit points are less than half of its maximum. On a fail, the creature takes 4d10 necrotic damage and gains 1 level of exhaustion, otherwise they only take half damage. Your are healed for half of the total damage dealt.