Alpha Wave Deck
Let the spectator name any word. It could be the most important person in his life, his first love, a product or company name.
Before he tells you the word, you take out the Alphabet Deck that you prepared for this occasion and remove the cards from the pack. He shows a deck of letter cards, where every letter exists twice in it. As there are 26 letters in the alphabet, these two sets result in a full deck of 52 cards.
Remove these letters from the pack to build this name. Turn over the deck and spread it to show that you used a blue backed Alphabet Deck. Then turn over the removed card to show that all of them are red backed. A perfect and inexplicable prediction.
The deck allows both presentation; red cards in a blue deck as well as blue cards in a red deck.