This is the most direct and clean solution to a brainwave deck ever.

• You take a red game out of a red box (also available with a blue back/box).
• You can show all the front sides because you really have a complete game in your hands.
• Have your spectator name any card, or better yet, ask three spectators for any three cards.
• No force, no initiated spectators, no complicated grips!
• Strip out the deck and find the three selected cards.
• Separate the three cards.
• Turn over the deck and show a complete red deck.
• Then, card by card, turn over the selected cards and show that the selections have the only blue backs!

This is the cleanest, fairest and simplest brainwave effect we know.
Of course, other presentations are possible, for example, simply showing a card with a blue back. You can find the selected cards yourself from the back and identify them as blue, since the backs are marked. Only your imagination is the limit. It's best to watch the demo video.