Cowskull's Chain

An ethereal chain connects two targets. One creature that you can see within range makes a WIS save. On a failed save, the target has Disadvantage on attack rolls against creatures other than one of your allied creatures within 30ft that becomes the focus of this spell, and it can’t willingly move to a space that is more than 30 feet away from the targeted ally.

The spell ends if the targeted ally makes an attack roll against a creature other than the target, if they cast a spell on an enemy other than the target, if you or another ally of yours damages the target, or if your ally ends their turn more than 30 feet away from the target.