Magic: The Gathering x Lord of the Rings crossover set Tales of Middle-earth contains a single copy of the One Ring card that was hidden somewhere in a collector booster pack released in an English-language country. The anticipation for this golden ticket of a card resulted in one shop offering a million dollars for it before the set was even released.
The card has now been found, and card-grading service Professional Sports Authenticator issued a certificate for it, as well as a grading of "mint 9". Given that the whole point of grading cards is comparing them to others, the idea of grading a unique card is pretty pointless. I can only assume they gave it a 9 out of 10 to leave room for possible improvement in the sequel.
