How does the Locking or Locked Reels feature work in slots?

One of the ways that slots development companies like to offer bonuses to players is through using a way to manipulate what happens with arguably the most important aspect of any slot game; the reels.

We have symbols that can be used for a variety of different symbols (Wilds) and in the good old days of slot gaming, long before the digital age, there used to be features such as Nudge (which would allow you to move a reel up or down one space per nudge) and Hold features (which you can still find on many slots today where one or more reels are held in place for the following spin or respin).

However, there are many different ways in which you can use the reels and the symbols on them to help (or hinder) a player's chances of landing a win but one of the less common ways to do this is through the use of Locking or Locked Reels.

It is relatively easy to understand how the Locking Reels symbol came about. When playing a slot game, if your reels show the same three symbols, usually from left to right across the reels, then you are likely to win on at least one pay line, if not many more, depending on the number of lines or ways to win in the game and how the symbols are arranged on the reels.

Clearly having two or more reels that showed the same symbols on a spin would be a positive for players and thus Locked Reels were developed.

Let's now take a look in a little more detail at the bonus and how it is utilised in the relatively small number of slot games that offer the feature.

What are Locked/Locking Reels?

In the simplest of terms, Locked Reels are a group of two or more reels that either on a standard spin, or more frequently when a bonus feature is triggered, will see those two reels linked together and display the same symbols in the same order. This means of course that when the reels come to a halt, the reels will display the same symbols.

Seeing as slot games are essentially about achieving matching patterns of symbols across the reels, the more Locked Reels you have in a spin, then the better the chances are for the player of landing a win. If you can land the first three reels as locked reels, or the first four, or all five, then you are guaranteed to land a win.

Locked Reels can easily be confused for other bonus features. In the famous Microgaming slot, John Carpenter's Halloween, for example, one of the features of the game is that the reels are set up in a 3x3x4x4x4 set up with the 4x4x4 set of reels linked together and able to move across the reels.

However, these are not locked reels as the reels that are part of that 4x4x4 block of reels do not display the same symbols at all times. They can land Jumbo Symbols which cover the entire three reels within the group, but in Locked Reels, the symbols displayed by the reels are the same at all times.

So it is important to note the difference here between a group of reels that are grouped together and may move across the reels (I'd call these moving reels or roaming reels) and those which are genuinely 'locked' together and display the same symbol when the spin concludes.

Another common feature of Locked Reels games is that the Locked Reels tend to be adjacent to each other, but it is not necessarily the same reels that lock together each time. On one trigger of the bonus, the third and fourth reels may lock together, whereas on another you may find the second, third and fourth reels lock together. On others you may land just the fourth and fifth.

By doing this, the bonus has greater variance for players (or perhaps more-so for the casino) and means that if the bonus triggers, players are not always guaranteed a big win, which is something you need to consider when playing games with this feature. Which brings us very neatly onto the next point.

Are Locked Reels beneficial to the player?

In general, Locked Reels can be very beneficial to the player, although the value of the feature is determined by three factors. These are:

• The number of reels that become Locked together in the spin.
• The position of those reels.
• The symbols that are displayed by the Locked Reels when the spin ends.

In the first instance, the greater the number of locked reels that spin together in a game, then generally the better the chances are for a player to land at least some kind of win. Having two locked reels is nowhere near as likely to generate a bigger value win than having three, four or even five locked reels (the latter of which will likely generate a big win for the player, assuming that the slot is a five reel game).

When not all reels are linked together in a Locked Reel bonus, then the position of those that are within the game is crucial and the general rule of thumb here is that the more the Locked Reels are located to the left of the reels and especially if the first reel is part of the group of Locked Reels, then the better it is for players.

It is much easier to hit a win with two Locked Reels if they are on the first and second or even second and third reels in the game, than they are if they are located on the third, fourth or fifth reels.

Finally, as with any spin on a slot game, the symbols that are displayed on the outcome of the Locked Reel spin are key to deciding how valuable the win is. Get lower value symbols and even multiple pay line wins can be small. Hit higher value symbols, or better still Wild symbols, and you will see the value of your payout increase. Your payout can also increase considerably if your Locked Reels contain stacked symbols as this can trigger multiple pay line wins from the spin.

Generally, Locked Reels is a very positive benefit to players, but it can also be a frustration too when you land two or three Locked Reels in a great position with a chance to win big, but then the other reels land and do not match up. This does happen relatively frequently in these games, but even so, the bonus is still one of the better and more valuable ones for players to access.

Some games offer players the chance to 'lock' reels before they spin. This is essentially the same as using the old "Hold" feature on older style slot games. There is usually a fee that the player needs to pay for a spin with the chosen slot held. While this is not the same as the Locked Reels we have here, we have mentioned it because it is obviously similar and some slots use the term "Locked Reels" or "Reel Lock" to describe this bonus too.

In which Microgaming games can I experience Locked/Locking Reels?

There are not a great deal of slot games available that feature the Locking or Locked Reels bonus, but the ones that we can confirm do we have listed below for you to try the feature out for yourself.

• Lock a Luck - Developed by All41 Studios, this is a 5x3 reel, 243 Ways to Win slot that features two Locked Reels on every spin which are located at random across the reels. However, on random spins, the two Locked Reels can randomly expand to incorporate three, four or five reels and of course, the more reels you can lock together and the more they are to the left of the reels then the better it tends to be for players. With a jackpot of 320,000, the slot also offers a sizeable jackpot prize.
• Book of Oz Lock 'N Spin - This slot allows you to Hold any of the reels in the game for a set price for the next spin and it calls this bonus the Locked Reels feature. This is a different feature to the main Locked Reels feature outlined above but you can lock consecutive reels together, which is in essence what the standard Locked Reels bonus does too.

As you can see, Locked Reels are not extensively used across Microgaming slots at the moment but I do think it is a bonus which could be used on future releases and I would be surprised not to see a few more games hit casinos that offer this feature in the months and years to come.