Interestingly, we've had different backs for the same front considered to be different cards, different grades of the same card to be considered different cards, and even a print scrap, which is apparently considered to be a different card from the production version.
So the rarest T206 Wagner is actually the Wagner card with a print variation different from all the rest, as well as the rarest slab: the Wagner belonging to these two fellows (no free advertising to the doofus who created the slab).
