Gambler's Buckler

This beaten buckler emblazoned with a horseshoe seems to say, "No matter how you stack the deck, eventually all luck runs out."

+1 Buckler that allows enemies that would have missed to hit, for each hit that you allow to strike you, you gain an automatic hit on the instigator of that attack, as if it were an attack of opportunity (but does not use it up). This effect is only active when you are gaining AC from the buckler.