Window to the Future by Henry Evans

The effect starts with the magician placing a group of cards as a prediction into a clear glass cup, then a different colored back deck is introduced.

The deck is shuffled by the magician and the participant, and then split into several random piles consisting of different amounts of cards.

The magician invites the participant to freely choose any packet, shuffle it, and then count the cards. The first effect happens when the amount of cards in the freely chosen packet matches the number of prediction cards.

The second effect occurs when not only the amount matches, but also the exact value and exact order of the cards matches the prediction cards!