Messing up with the spectator

You can use any deck for this trick, which the spectator can shuffle.

Say you and your spectator will each one after another create 6 piles. You have to do 2 piles of 5 cards, and remember where they are.

Ask the spectator to choose a pile, take half of it, and look at the bottom card. You must now put this half-packet on the 5-cards pile.

With the deck face-up, deal 2 piles on the table. The spectator's card will be the 6th card dealt, remember it. Ask your spectator which pile you have to get rid of.

While squaring up the correct pile face-down, grab a break under the 3-top cards. Flip the first card, and ask the spectator if this is their card. They can lie or tell the truth. Eliminate it. Now do a double lift, to show their card. Eliminate the arbitrary card on top of it.

To "go faster", deal 2 piles on the table face-down, and using the magician's choice, keep the one with their card, which will be on the bottom.

If you have more than 5 cards, ask the spectator to eliminate cards. Make their card go in the second position, by doing an overhand shuffle and peeling off 3 cards.

Finally, do a deal and a duck. You will end up with the spectator's selected card, which they think is eliminated.