Opponents can cast spells only as though they were sorceries and can attack Teferi as though he were you. Put 4 loyalty (use counters) on Teferi. Any damage he suffers depletes that much loyalty. If Teferi has no loyalty, he abandons you. During your turn, you may add 1 loyalty to allow you to cast sorceries as though they were instants until your next turn; or you may spend 3 loyalty, then the owner of target artifact, creature, or enchantment returns it to hand and you draw a card. Any enchantments on it are discarded.