Thinkgood’s Thaumaturgical Transference

As an action, you touch a willing creature and create an arcane conduit between you and the target until the spell ends. While the target is within 60 feet of you they can choose to use your spell slots as if they were their own. When they do so you expend the spell slot as if you had cast the spell yourself. The strain of such a transfer takes its toll, and you take 1d6 force damage every time the target uses one of your spell slots.

The target can only use spell slots that you have not yet expended and none of the slots they use can be 5th level or higher. They cannot cast a spell they do not know or do not have prepared. The target must know at least one spell to begin with or this spell fails.

The spell ends if you drop to 0 hit points or if you and the target become separated by more than 60 feet. It also ends if the spell is cast again on either of the connected creatures. You can also dismiss the spell as an action.