Ghost Touch 2014

You create an intangible, cadaverous hand that latches onto a creature within range, assailing its life force. Make a ranged spell attack against the target. On a hit, the target takes 1d8 necrotic damage, and it can’t regain hit points until the start of your next turn.

If you hit an undead target, it has disadvantage on attack rolls against you until the end of your next turn.

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