This is an effect that I use to practice the Erdnase system of cull shuffling.
Effect: The performer shuffles a deck of cards and then has the spectator shuffle them as well. The performer then takes the deck back and ribbon spreads the deck face up on the table, remarking that the deck is now well shuffled as the spectator can see.
Picking up the deck the performer give the deck another shuffle, overhand shuffling the cards.
Then explaining how card sharps always need to find some good cards for their hand, the performer turns over the top four cards, revealing the Aces.
Method: The Aces begin on top of the deck. Do an in-faro shuffle so the Aces are 2nd, 4th, 6th, and 8th from the top. Hand the deck to the spectator and have them to one riffle shuffle. Do not let them do an overhand shuffle. After one riffle shuffle the Aces with be distributed among the top cards of the deck.
Ribbon spread the deck face up to show the deck shuffled. With the cards spread quickly note the location of the aces as a series of four digits. For example, if the aces were in the 4th, 8th, 13th and 14th locations you would remember the numbers 4, 4, 5 and 1. Now pick up the deck and do the Erdnase system of culling those cards with an overhand shuffle, briefly:
- undercut half the deck, injog the first card and shuffle off
- cut at the injog run 3 and injog the 4th (Ace)
- run four (an ace is the last card run)
- Run one card outjogged and then three more (4 total)
- Throw the remaining cards on top
- Undercut at the outjog, keeping a break at the injog
- Run one, at the same time injog the top card of the deck with your left thumb
- Throw the cards above the break and shuffle off the remaining cards.
- Undercut at the injog and run one card (Ace)
There is now one ace on top and three on the bottom. Use either overhand shuffles or cuts to move the three aces from the bottom to the top of the deck.
