This deck of cards has a bar code printed on the edge of each card. Scanning these bar codes would reveal where every card is (or isn't - if cards are missing.) Think card magic. 1/ https://t.co/lSMjvD7Jy2

This deck of cards has a bar code printed on the edge of each card. Scanning these bar codes would reveal where every card is (or isn't - if cards are missing.) Think card magic. 1/