Tordek's Undead Shield

As you channel the energy of undeath you can choose 1 undead under your control to take damage for you, your undead will take damage equal to that of which you would have taken up to a maximum of its current hit points, if the damage total exceeds the current hit points of the undead creature any remaining damage will be taken by the caster of the shield. At higher levels you can choose 1 extra undead under your control for the spell to effect for every level above 4th that it is casted.