Kings over Queens
by Peter Pellikaan

You show a packet of four black kings with blue backs and you place them face-down on the table. You further show four red queens. Waving the queens face-up over the face-down kings suddenly turns them all face-down as well. Another magical gesture and the four red queens are now four black kings. You place the packs together and suddenly the cards magically mix. Finally, you show all cards individually as totally normal except that the backs of the queens have now suddenly turned to red. No additional cards. No double-facers and no double-backers or other gimmicked cards.

1st edition 2022, video 2:42.