R. Paul Wilson On: Marking Cards For Fun (And Profit)

R. Paul Wilson On: Marking Cards For Fun (And Profit)

As a magician, I’m always being accused of using marked cards. A simple strategy I’ve evolved to address this is to open brand-new decks and give the cards away at the end of a performance as a demonstration of fairness.

This usually satisfies suspicious audience members, but the truth is I could hand them one of a dozen types of marked decks with complete confidence they would never suspect, let alone detect the secret information on those cards.

That’s not to say that all marked decks are created equal.

Deck of cards
Image: by Sagar Soneji on Pexels

Several types are extremely easy to identify if you know what to look for and many are sold as novelty items for “entertainment purposes only” with a slip of paper or a printed card teaching how to read the code.

More sophisticated systems depend on learning to see variations in patterns, colours or shade on the surfaces of cards. But not all marked cards depend on sight and some are designed to be read by touch alone.

Others are made to work with hidden cameras, sensors or other concealed technology and cannot be detected without the help of an appropriate device.

Some systems might be glaringly obvious to those who know yet utterly invisible to casual players.

Preparing marked cards can happen in several ways but an important question is: how do cheaters get them into a game? They can’t just pull a deck out of their pocket and say “hey, let’s play with these!” or they may take the blame if the dirty work is later discovered.

In this piece, we’re going to discuss pre-prepared marking systems.

The most obvious method is to apply marks to a legitimate deck. There are many ways to do this that require varying degrees of skill.

Obviously, cheaters spend a lot of time practicing these systems and some become so good at marking cards, their work should be displayed in a gallery!

Subtly Changing the Back Design of Cards

“Block out work” uses inks or paints that can subtly adjust the back design of a card to signal suit and/or value. A needle can also be use to apply “scratch work” to a card and I’ve seen intricate work applied to the backs of cards that would be worthy of a master engraver.

Marked playing cards
Image: Casino.org – An exaggerated example of how cheaters can change the deck pattern.

Partially invisible inks have long been a favourite method of cheaters who train their eyes to see what others cannot. Green and yellow pigments on red-backed playing cards can be applied in such a manner that only those who are looking for the marks will notice. I’ve seen heavily marked versions of these decks that looked obvious to me yet were undetectable to the untrained eye.

Some “work” is completely invisible to the human eye and requires special glasses or contact lenses to see – but we’ll discuss those methods another time.

Cheaters Make Special “Juice” to Change Pigment Shades

“Juice” is a simple recipe for creating variations in the shade of pigments on the backs of certain card designs.

How the juice is made and how it’s applied are secrets passed from one mechanic to another. The strength of that juice depends on the skill of the cheater when reading patterns of blotches on the backs of cards.

To a well-trained eye, even super-subtle juice can be read from across a crowded room but if the marks are too heavy, honest players might notice something about the cards that isn’t quite right.

Professional juice is impossible to detect without the required training.

Marked cards
Image: Casino.org – An exaggerated example of how cheaters can mark the deck pattern. This would be done far more subtly and therefore invisible to an untrained eye.

A Story to Prove It…

One morning, I had breakfast with two friends, one of whom had made some expert juice for us to add to our collections.

The marked decks were red-backed Bee cards with a simple diamond pattern on the back and my friend’s work was exceptional. My other friend was struggling to read the marks, so I handed him my deck to try. What he didn’t realise was that I happened to have an unmarked Bee deck with me and had switched the marked cards we were looking at for unmarked cards!

He struggled to see the juice that wasn’t there, then held up a card for us to read from across the table. My friend who had made the marked decks immediately called it and was a hundred percent right! I was completely fooled until he repeated the feat several times and realised he could see the cards being held up because the restaurant wall was mirrored!

We let our friend in on the joke and fortunately for me, he didn’t drive me into the desert with a shovel in the trunk.

Using “Punch Work” to Make Cards Feel Different

The shapes of cards can be changed by removing hair-like slithers from the edges of cards for use with various dishonest techniques. Shaved cards can be located while shuffling or controlled into or out of a player’s hand.

“Punch work” is where a cheater creates tiny bumps on the back or face of a card for the purpose of identifying those cards during a deal, using the sense of touch alone. There are devices designed to make perfect, imperceptible little points on a playing card but many cheaters make their own or discover perfect substitutes they can buy anywhere.

One professional shared his method with me late one night in Las Vegas: we walked into a well-known store and asked for a common medical item that allowed him to not only punch an entire deck quickly, it ensured every little bump was identical. This last part was essential since his method was to sneak the game deck into the bathroom while everyone took a break and punch the cards he wanted in seconds without accidentally pushing a needle clear through one of the cards.

More importantly, if he was suspected of anything, the device he used would appear to be for his medical condition, whereas a typical cheater’s punch would be obvious evidence of foul play.

Punch work is commonly used with an expert second deal with bumps so tiny that that you’d be lucky to feel them, even if you were trying to find something.

Punch deals require a sense of touch combined with perfect timing to execute a second deal when a marked/desired card arrives on top.

The most direct application is to deal cards honestly until you feel a punched card, then deal the second card until you reach the player you want to give the marked card to; then repeat for each round of play.

In fact, there are much more sophisticated ways to use a punched deck.

Imagine a deck that signalled whenever you dealt a high card during a game of Kansas City Lowball. You now know whose hand is broken by one or more high cards and which player might be playing a seven low.

Information alone should be enough to give a decent player an advantage so cheaters using punched card like this learn to deal quickly and fairly while feeling these tiny marks as they deal.

Re-Sealing a Deck of Cards to Look Brand New

Another consideration when making marked cards, is how to re-seal a deck without evidence of the contents being tampered with.

I’m here to tell you that this is both possible and in some cases, quite easy to do. With enough time, anyone can figure their way into a sealed deck that allows the box to be glued back together as if nothing had happened.

The cellophane wrapper, however, can be tricky but there are several solutions for that, too.

Many years ago, in a bar in Madrid, the topic of re-sealing decks came up while sharing ideas with a legendary Spanish card cheat. He told me he had a perfect solution that required no glue or special equipment and could easily be accomplished in almost any situation.

I’m not going to share that method with you (or anyone else for that matter – I was sworn to secrecy) but I can tell you this: XXXXXX took a sealed deck, popped it open, removed all the cards then re-sealed the box using a traditional method – but this left the frayed cellophane wrapper to deal with.

Smiling, XXXXXX removed two common items from his pocket and in ten seconds that box was re-sealed perfectly; the previously torn cellophane magically repaired.

I now possessed a perfectly sealed (empty) card box and a beautiful secret that I’ve used ever since.

The lesson here is simple: other than a few rank methods, a properly marked deck is hard to spot unless you know exactly what you’re looking for and how to see or feel that work.

If marked cards are being used against you, it might be easier to identify by how cheaters are acting than to discover the secret work on a professionally marked deck. In my experience, amateur cheaters have no idea how to employ a marked deck without making it blatantly obvious they’re reading both sides of the cards!

Other articles by R. Paul Wilson include card counting basics and top tips for carrying large sums of cash. Come back on September 23 for his next post that looks at advantage play in blackjack.