It's always easier and a little bit more deceptive if you perform a bottom deal with less than a full deck.
I was thinking of different ways to get in the position...the most notable being a game of poker where hands have already been dealt.
I wanted something quick and to the point so I played with the idea of just cutting off a small packet of cards and using roughly about 30 cards because there are about 30 days in a month.
Set up: one ace is on top three aces on bottom
Start out by false shuffling the deck or simply riffle shuffle without disturbing the top and bottom stock.
Ask them to lift off about 20 cards estimating less than half the deck.
Immediately after they lift off the packet of cards perform a sideslip and push the bottom ace into your right hand and load this is on top of the deck under a squaring motion.
Essentially you are just moving the bottom card to the top.
Now a card is freely selected from the remainder of the cards in your hand. This card is controlled to the bottom by your favorite method. In the video I use a simple spread cull controlling the card to the bottom.
You ask them what day they were born because you have about 30 cards in your hand and "there are about 30 days a month."
Deal to the number that they name and perform a bottom deal when you get to their number.
The card that you bottom deal will be the selection.
As you are revealing the selected card get a break above the bottom card of the deck by buckling or using a pinky pulldown.
Flip the selection facedown on top of the deck and grab the entire deck above the break leaving the bottom card in your left hand while simultaneously placing the deck off to your left with your right hand.
This is essentially the mechanics of the jinx switch.
Flick the card in your hand and turn it face up revealing an ace
Flip the small packet of dealt cards face up revealing an ace.
Flip the top card over of the original packet that they cut and that will be an ace.
Finally flip over the packet that you placed off to the left revealing the last Ace.
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