Whose trick is this?
I think it's a Helder Guimaraes, but maybe a Benjamin Earl, and I want to properly attribute it and can't remember the name of the trick/author.
Effect: Four identical cards are shown face up, then each time they are displayed one additional card has been "magically" flipped and now shows its back. Once all four have been flipped to show their backs just one is turned face up, but on the mext display all four are revealed to be face up, not just the one.
I can perform it, not asking for a method, just the correct attribution.