The Ultimate Six Deck Shuffle

By Bill Zender

(This article was printed in Casino Enterprise Management Magazine’s May 2006 edition)

For a number of decades now casino executives have been try to come up with a multiple deck shuffle that will provide two important elements; a random non-trackable shuffle, and a shuffle that doesn’t take all day to complete.  Usually the one element did not fit with the other and many an executive had to make the decision; will our casino benefit more from a quick multiple deck shuffle or a multiple deck shuffle that is difficult to shuffle track?

Sadly, in most case the modern executive opts for the all day shuffle over the quick shuffle.  Why?  Because they do not want to come to work one day and discover a sophisticated shuffle tracking team hammered their high limit multi-deck blackjack game for thousands of dollars.  How can the live games manager explain this loss to their executive committee who does not think to focus on the advantages of getting more gaming results from a fast shuffle?  Do they think about all the revenue the games manager theoretically will win by get several more hands out per game per hour?  No, they’re concerned about why the casino allowed advantage players to walk away with a nice portion of the casino’s bottom-line.

In the past it has been reasoned that the only true non-trackable multi-deck shuffle can only by attained through the use of a shuffling machine.  The shuffling machines mix or shuffle the cards in one total group; as if giant hands were able to riffle six or eight decks together like they were a single deck.  When all cards are riffled together into one group all ability to track a shuffle is lost.  Why? Because the cards are no longer segregated into different zones or tracks like we see in a standard four, six, or eight-deck shuffle.  Once a group of cards are properly riffled together any ability to track slugs of cards through the shuffle is lost.  Unfortunately, most dealers’ dexterous ability is limited to shuffle a double deck.  Any shuffle containing more then two decks will have to be manually riffle shuffled in separate tracks, and any time this segmented shuffle process is done the shuffle can be zoned tracked.

Subsequently, in an attempt to defeat advantage players shuffle tracking multi-deck shuffles, more complicated and time wasting shuffles were created.  Criss-cross multi-grab shuffles with several riffle shuffle passes became popular, as well as the card zone diluting “stutter” or stepladder shuffle.  All were complicated shuffles that took the normal dealer anywhere from 3 to 4 minutes to complete while only providing a slight obstacle to the knowledgeable player.  Even the complicated multi-pass stutter shuffle could be exploited and is more vulnerable to other forms of shuffle tracking such as sequential tracking and key card tracking.  Finally the industry had to accept the inevitable; regardless of the number of passes and sophistication of the shuffle scheme the multi-deck shuffle could always be tract to some extent.  At least we thought that way until recently.

A couple of months ago I was putting the finishing touches on my latest book, “Advantage Play for the Casino Executive”, and I was thinking about my latest chapter on shuffle tracking.  I had just mapped the manual six-deck shuffle we used at the Aladdin Hotel/Casino back in the 90’s, and was trying to come up with an improvement to the shuffle without adding more time to the process.   The old Aladdin shuffle required the dealer to break the six decks in three two-deck stacks and then perform a quick strip to each two-deck stack.  We realized that a stripping process that was performed varying in three, four, or five parts threw a virtual “monkey wrench” into any shuffle tracker’s mapping process.  By adding this variable to the shuffle we were practically guaranteed that the only tracking team that could hurt use had to use a tracking computer and input the varying stripping actions the best as possible, and these groups are extremely rare.

Then it dawned on me; what if we had substituted a riffle shuffle for the stripping action?  The riffle would not only be better then the strip it would turn the two-deck portions into one zone.  Then when the decks are shuffled together their card distribution would be equal.  If this holds true then the shuffle wouldn’t be trackable.  Had I stumbled across the solution to the problem?

The solution however was too simple.  Why hadn’t we thought of this before?  Could the two-deck riffles defeat shuffle tracking?  It seemed too easy.  Then I approach several other gaming consultants with the shuffle and they all came up with the same conclusion; performed correctly it eliminated zone shuffle tracking.  I also ran this shuffle past an informal focus group at the Seven Feathers Resort/casino in Oregon.  Surveillance director Jeff Murphy, who arguably has one of the best trained surveillance departments in the industry, allowed Bob Del Rossi and myself to run the shuffle past his people.  Their conclusion was the same as ours, that the shuffle can’t be zone tracked.  They also estimated that the shuffle was extremely quick, taking between 75 to 90 seconds to complete from the time the cut-offs are removed from the shoe till the cards are presented for cutting. 

I look at this shuffle as a computer programmer looks at shareware.  Since this shuffle is a collection of components that are already being used in the industry, I don’t feel I have any right of ownership over its formula, so I’m releasing it for everyone to copy and use.  If you implement this shuffle in you’re casino the exact way I describe it in this article, you will have a quick and safe shuffle that will increase your blackjack revenue in the long run.

Six-Deck Multiple Shuffle

Step 1: Regardless of deck penetration place cut-offs on top of discards (no plugging)

You will no longer have to plug the cut-offs.  Just place them on top off the discards.  Eliminating the plugging action will save time and speed the shuffle along.

Step 2: Break six decks into three two-deck stacks

If you want to use this shuffle with four-deck game, break into two two-deck stacks, and for an eight-deck game, break into four two-deck stacks.

Step 3: Take each two-deck stack and complete riffle, box, & riffle

The riffle shuffle mixes the two deck segments together and destroys any tracking information of 25, 35, or 50 card trackable zone information.  All tracking information is diluted into the entire two decks.  The addition of the box helps mix the cards.  Because a two-deck segment is shuffled together the likelihood of top or bottoming clumping is high, especially with dealers with smaller hands.  By boxing the deck between riffle shuffles (taking one third of the cards from the bottom and placing them on top) will prevent any clumping problem.

Step 4: Take approximately 35 cards off each of the three stack, complete a riffle, strip (5 part strip), & riffle, and place in a separate stack on the table

This process will combine all stacks together equally.  Thirty-five card grab sizes from each of the three stacks produces 104 cards, or a two-deck group for shuffling.  A five part strip is added between the two riffle shuffles.  This will destroy possible sequential tracking and will put a huge dent in a player’s ability to accurately use key cards to locate the reappearance of an ace target card.  (Note: Four deck shuffles require 50 card grab sizes from the two two-deck stacks and eight deck shuffles require 25 card grabs from each of the four two-deck stacks.)

Step 5: Continue Step 4 until all cards in the three stacks are shuffled

Following is a six deck mapping illustration on how the cards appear once the three stacks are shuffled together.  Note: The mapping uses 50 card tracking zones.

As you can see there aren’t trackable zones that can be used after the riffle shuffles of the two-deck stacks, and an equal mix from the three stacks.  However, like any shuffle there lies an Achilles Heel; an area where failure to follow the proper shuffling sequence could result in the shuffle being tracked.  This could occur if the dealer does not pay particular care to the grab sizes during the mixing of the three two-deck stacks or performs a rather clumpy shuffle creating slugs on the top and/or bottom of a shuffled group of cards.

After several trials it has been determined that grab size mistakes of five to ten cards have very little effect on the shuffle.  Even if a trackable zone of 100 cards is plus 15 or minus 15, grab size errors would have to exceed fifteen cards, almost half (more or less) the required grab size, before a shuffle track could expect to gain ½ percent advantage of the 100 card playable zone.  With some degree of diligence on the dealers and the floor staff the chance of this happening is practically non-existent.

Whenever more then a single deck of cards are shuffled together there’s a good chance that card clumping will occur.  This is the reason why there is a box placed between the shuffles during the first shuffling stages.  During the three two-deck stack shuffling process the box has been replaced by a strip.  The stripping process is important because it destroys the order of cards and renders sequential shuffle tracking and key card tracking useless.  However, the deck stripping process has some draw backs when it comes to protecting against a top/bottom clump shuffle.  It’s important that your dealers are given training on the proper methods to riffle a 100 plus group of cards.  Taking time to explain the mechanics of the riffle shuffle and strip will save you problems in the long run.  In any case, don’t place too much worry on clumping.  The clumps on the bottom or top of the shuffled group would have to exceed 10 to 15 cards before they could be exploited.

Note: Do not arbitrarily decide to add a box and additional riffle shuffle to step 4 of this shuffle.  The time wasted by performing the additional box/riffle will cost more in revenue due to time lost then could be saved from eliminating any possible clumping.