card. The magician pulls the deck out and fans the cards face down, then spreads through the deck until a single face-up card is discovered, which turns out to be the spectator's card. For the grand finale the magician explains that he or she actually knew ahead of time which card the spectator would select, rather than having secretly turned it over during the performance. He or she then proceeds to prove this by turning the spectator's card over and revealing that the card in question features a different backing pattern than every other card in the deck, suggesting to the audience that the magician may possess powers of extrasensory perception. An inverse handling of the Brainwave deck is the X Deck, originally invented by Jay Sankey and identical to the Invisible Deck, but with the odd cards having an X on them. Both decks are meant to convey the idea that the magician did not perform the intended effect through the use of sleight of hand. Non-standard decks The following are not trick decks per se, but the cards they contain may be combined with a normal deck (or a packet of cards from a regular deck) in order to perform specific tricks. Gaff deck A gaff deck is a deck that contains cards used in conjunction with a normal deck. For the most part gaffed cards have the same back pattern as a standard deck of cards, but the faces are changed in various unique ways; for example, there may be two "3½ of clubs" cards, which might be used to split a 7 of clubs into two cards if called for. Gaff cards are sometimes included as bonus cards with a regular deck. Blank deck A blank deck has the standard backs (all identical) but lacks faces. That is, there are no values such as 5 of hearts on any of the cards. Double blank deck All cards are completely blank on both sides. Double faced deck All cards have faces on both sides. Double back deck All cards have the standard backs on both sides. Standard deck setups There are many ways to order a deck so that the magician can perform special tricks. It is possible to use a stack, or ordered deck, to determine what card the spectator cut to. A popular stack to use for this is a Si Stebbins Stack. To make