With Xerox deck you can show the most visual and amazing multiple transformation of an entire deck of cards.
You show a regular red back deck with indifferent cards on the faces. You only have to add a selected card from a blue deck, let's say the three of spades, and instantly all the cards are three of spades. If that's not enough, all the backs change into blue. After this jaw dropping double transformation, with only taking out the selected card (the three of spades), the deck goes back to regular, with red backs and indifferent cards on the face.