Draining Grasp

Necromantic cold energy envelops your hand to drain the lifeforce of a creature you try to touch. Make a melee spell attack against the target. Due to the hampering of mobility caused by metallic armors you have advantage on the attack roll if the target is wearing armor made of metal. On a hit, the target takes 1d8 necrotic damage, and it can't take reactions until the start of its next turn.

The spell's damage increases by 1d8 when you reach 5th level (2d8), 11th level (3d8), and 17th level (4d8).