Very easy to do and instant reset
You show a small plastic sculpture as your prediction and some cards with super heroes names on them.
A spectator selects a card/superhero
You light up the sculpture with the light of your smartphone and the shadow on the wall reveals a question mark.
You visibly rotate the sculpture and the question mark morph into a face. It is not the super hero the spectator selected. You pretend it's the correct guy that didn't put his costume... You then shake slightly the light and the shadow change into their superhero.
Comes with plastic gimmick + online video explanation