It’s a common question: “What games can’t be cheated on?”

It’s a tough issue to answer because in my experience, cheaters and advantage players can compromise the security of any game, and the more confident someone is about the safety of their games, the more worried I am that they aren’t keeping a close enough eye on them.

Slot machines, for example, take up most of the floor space at contemporary high-end casino resorts and are meticulously monitored, not only from the floor or the eye in the sky, but also internally, with anomalous activity recorded automatically.

Although these computers have been successfully attacked, the more security measures they take, the more likely it is that a critical flaw will be discovered and exploited.

Since they first appeared, slot machines have been the scene of many a cat-and-mouse game between cheaters and the house.

Mechanical Manipulation of Old Slot Machines

Let’s start in the not-too-distant past when slot machines were hardly more sophisticated than clockwork.

Many vulnerabilities in early machines were eventually exploited and exposed as time went on. One of my favorites was the option to “pop the arm” of a one-armed bandit following a winning spin.

The gear was cocked and the wheels began to rotate as the arm was lowered. Slapping the arm kicked it past the gear, trapping the reels in their previous position, such that when the arm returned to its starting position, the reels registered another (same) win, even though the tension hadn’t been released, which would have randomized the outcome.

To get access to the interior mechanism, where weights could be added, gears filed, and any possible technique of influencing an outcome attempted, the locks were quickly picked because they were poorly built and easily accessible.

When the security of the computers improved and their mechanical faults were fixed, the cheats became more resourceful.

Using a Bulb to Cheat The Light

To regulate the rate of coin dispensing, a light sensor was used, which detected each coin as it passed by, temporarily blocking the light. This rendered a previously-used cheating technique useless, although it did inspire a novel approach.

The number of times a coin was deposited into the tray was recorded by a tiny bulb attached to the end of a thin plastic piece that could slide into the hopper and make contact with the sensor.

The payment system recorded one cent being handed out each time the bulb was damaged. When the desired quantity of coins had been ejected, the machine would continue mechanically extracting coins from within and spitting them out.

The hidden light bulb was placed in front of the sensor and activated whenever the machine dispensed money. Since the crook was shining his own device into the sensor, the coins were now falling out of the bank and into the tray, but behind the light!

This meant that until the machine tipped over, coins would continue to fly out of it.

Skilled slot robbers rapidly learned how long to play the light to elicit only a marginal increase in the number of coins ejected each time the machine paid out.

As a result, machines have been updated to include a plastic guard with a hinge that can be swung in front of the sensor from below, rendering “the light” scam futile.

The cheats, being cheaters, discovered a way around that.

In all likelihood, the new setup was defeated within five minutes.

Fixing The Light Cheat Lead to “The Monkey’s Paw”

Casinos implemented this fix to prevent players from exploiting a flaw in the light, but it also made it simpler to tamper with payouts.

This new cheating mechanism was emptying machines on casino floors while slot machine manufacturers were gleefully adding the hinged guard into every new machine on the market.

In contrast to the “light,” which required soldering and connection to a battery and looked like what it was — a shady gaming device — the Monkey’s Paw was delightfully straightforward.

The “paw” was just a piece of thick, stiff wire bent to fit the machine’s interior design, with the end able to swiftly mate with the underside of the plastic guard that was hinged to prevent the light from being turned on.

As coins were being dumped, the cheaters simply moved the guard up and out of the way of the sensor.

The mechanism would spew out coins until the required sum was paid since it was a spinning device that carried coins out and over, passing the sensor to be counted. It was necessary to play the paw in and out carefully to not cause the machine to tilt and alert security.

The cheaters effectively extended the time each coin broke the light from the sensor’s vantage point. Each time the light was snuffed out, it looked like a single penny had fallen, but several had been let through.

By blocking the sensor for a longer period, it is clear that the technology developed to safeguard slot machines from a hidden light source is even more successful.

Coins Out – But That Didn’t Stop The Cheaters

Slot robbers could not milk machines for more coins when their use was phased out, and casinos were quieter without the clamor of falling silver dollars.

Players fed paper money into the new coin-less machines and were given a bar code to cash out at a cash register or a different machine connected to the network.

A few brazen scam artists would appear to help consumers cash out while switching out their substantial win or cash-out for a smaller sum on a slip of paper that looked exactly the same.

Since casinos are usually careful to prevent other people from exploiting their consumers, these men were immediately identified and imprisoned.

Bill readers and cashout slips become a target for cheats in the long run.

A simple device, adapted from a pocket garage door opener, was used to discover and exploit a vulnerability in the electronic bill readers.

When a bill was inserted into the reader, the thin, flat wire protruding from the gadget would slide under the paper. Every time the button was pressed, a signal was sent to the reader, instructing it to record a $100 bill.

The cheater would put in one dollar, click the button nine hundred times (anything beyond that would raise suspicion with management), and then leave the machine for a shill to take over. They’d stay for an hour or more, playing until they ran out of imaginary currency or won some real stuff.

The plant would then withdraw cash, present the paper to the teller, and walk away with several hundred dollars. To ensure thousands of dollars for a “night on the town,” thieves would rob multiple businesses and machines simultaneously.

Cats Napping

The ongoing growth of cheating techniques reflects the constant cat-and-mouse game performed between casinos and those who are determined to beat them.

Since the people who break through, under, or over walls think differently than the people who create them, putting all of one’s trust in a single security process is foolish.

During routine maintenance, a savvy casino worker reprogrammed a few slot machines that had been equipped with microchips.

Naturally, his cronies no longer relied on their good fortune.

I once witnessed firsthand the bill above reader trick, only hours before hearing a business tell its clients that it was “impossible” at a casino conference.

The lesson is this:

A loophole exists in every policy, including in online slot games. Someone just needs to see things from a different angle (and motivation).