High Noon by Mark Cahill

The magician places a prediction on the table face down, and when it is turned
over it reads: “Your card is “12" cards down.”
The deck is spread showing the cards are mixed. A spectator then gives
the cards a cut and two completely free choices to either select the top
two cards, the bottom two, or even one from the top & one from the
bottom. When they do and the cards are totaled, as per the prediction that
very card will be 12 cards down from the top or the bottom every time.