Pariah by Daniel Madison

If you cannot change what you see change the way you see it.
The only enemy is the I inside.
If he can control his delusion, he can rule the world.
The spectator is given the deck and asked to shuffle and merely think of a card. Having removed the freely thought of card, the spectator is asked to write any freely thought of word on the card. The cards are returned to the box and the spectator inserts their signed card anywhere in the deck before closing it. The deck is instantly placed aside or in the performers pocket out of sight.
The performer instantly knows the freely thought of card.
The performer instantly knows the freely thought of word.
Without touching the deck again, the selected and signed card can be revealed anywhere the performer desires...sealed envelope, another sealed deck, another pocket, in the performers shoe etc.
All you need to make each device is a deck of cards. Each device can be made within minutes. Difficulty level 7/10. Each device will last as long as a regular deck would. For the anywhere revelation effect you'll ideally need to be wearing a suit jacket when performing. Can be made with any deck of cards within minutes.