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On this page, we’ll let you in on all the nitty-gritty details of slot features, from triggering symbols to bonus rounds to win boosters. We’ll use visuals, handy tables, real examples and a list of the top 10 slots with the best features to put theory into perspective. Read on for more!

Learn About Slot Features at JohnSlots!

This is your step by step guide to the best slot features, what they are and how they can help you win. To give you the most detailed rundown possible, we’ve covered topics concerning the types of features you’ll come across, how to recognise them and choose the best ones.

We’ve also got our casinos pros to compile a list of top online casinos where you can play slots with some of the exciting features any time you like.

Slot Features featured image on pink background

What are Slot Features?

Slot features are all the key components that make up a slot game. They are designed to make gameplay more exciting and to boost your wins. Think wilds, scatters, jackpot symbols, avalanche reels, free spins rounds, and random triggers. These are just some of the common features that you’ll find in most slot machines.

Slot machines with many features might look intimidating if you’ve never played a video slot before, but they are usually easy to understand once you’ve played the game. The more slots you play, the quicker you’ll recognise the features.

Read the Paytable

First, you’ll want to look for a paytable which displays the main symbols and bonus features involved in gameplay. You’ll then know immediately how much each symbol pays, what it does and how to activate the bonus round. Bonus rounds will also be explained in detail, so you know exactly what’s going on on the reels when you push the spin button.

The paytable will also tell you all about the paylines and what mechanic has been used to build the slot. Some will also indicate betting strategies and display key stats such as the RTP, hit rate, volatility and max win.

How Slot Features Enhance Slot Basics

Now on to the best part – playing the game! Any slot game starts working when you place your stakes and press the spin button. The reels will start spinning, and when they stop, you’ll see the outcome of your spin. Your aim is to line up winning symbols according to the paytable. Features in slots add an extra level of entertainment, over and above simply matching symbols.

Slot features make gameplay more interesting and they’re designed to help you get a payout. They can help by increasing your chances of spinning a winning combination of symbols. Wilds, Colossal Symbols and Reel Sync are just a few of the features that do this, but there are many more! Slot features can also give you guaranteed wins or trigger bonus rounds.

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Slot Mechanics

If slot features make your game more exciting, slot mechanics indicate the game’s potential. Unlike features, which are primarily there for entertainment, the mechanics of a slot reveal how the slot actually works.

Random Number Generator

One of the most frequently asked questions is whether land-based or online slot machines are rigged or not. And the simple answer is they’re not because each spin’s outcome is based on Random Number Generator (RNG).

That’s why slots are often referred to as games of luck. Any slot machine you choose generates thousands of random numbers per second. As soon as you press the spin button, the most recent random number will be used to determine whether you win or lose.

Payout Percentage

Another key stat to look out for in a slot game is its return to player (RTP) rate. RTP is a percentage of bets (on average) that the game will pay to a player in wins. So if the game has a 96% RTP, theoretically, every £1 you bet it will give you £0.96 back, and the casino keeps the rest – £0.04.

Every slot has an RTP set by the developer. Often they’ll release several versions of the same game with a different RTP rate which can vary between 95% – 97% or even higher. Online casinos will then choose which of the lot they want to host in their games lobby and that’s why it’s of utmost importance to check this info when choosing where to play a best RTP slot game.

In the UK, the developers are legally bound to include the RTP in their paytable or the game description alongside the volatility and hit rate. These two components are especially important in determining how risky your chosen slot is.


The game can be low volatility, meaning that the wins will roll in often, but they’ll be relatively small. Medium volatility indicates that the hit rate and payouts are set to a medium level. High volatility means that wins will be particularly tough to hit, but they could potentially be huge. The last math model is incredibly well-rated among seasoned players who choose to play games with massive potential payouts.

Types of Slot Features

The more slots you play, the more different types of slot features you’ll come by. Below we’ve listed some of the most popular, but you’ll soon discover that the game developers are in a constant battle to invent some new features or improve the existing ones.


Wilds are some of the most common symbol features in a slot game. They can be simple logos or appear as heroes of the slot, depending on the theme and the developer’s imagination. Wilds are mostly used as symbol substitutions to help you get a winning combination that otherwise wouldn’t be complete.

Gif of wild symbol slot feature

Wild Symbols Slot Feature

In the most basic slots, wilds usually substitute for all paying symbols except scatters and other special symbols such as jackpot symbols. But some more complex and bonus-rich slots like Testament from Play’n GO, will also have unique wild variations appearing during bonus rounds. In this particular game, you’ll find a range of wilds such as regular wilds, sticky wilds and spreading wilds.

Testament slot screenshot of the feature

Other types include jumping wilds, walking wilds, diagonal wilds, wild overlays and multiplier wilds. They pretty much do what they say, so it’s easy to understand their abilities. Checking the game’s paytable also helps to understand these symbols better.


Scatters are your besties in any slot game. It happens, but it’s rare for a slot not to have a scatter symbol. If that’s the case, they can sometimes be replaced with something else, like bonus symbols, which function in a similar or even identical way.

The reason the scatters are such great company is their ability to trigger bonus games, usually free spins, mini-games or any other bonus rounds. The game rules will tell you exactly how many scatter symbols you need to land to activate the bonus feature. It’s usually 3 or more scatters. Depending on the game, more scatters can award a bigger bonus, such as more free spins.

Gif of scatter slot feature

Scatter Symbols Slot Feature

In addition, Scatter symbols don’t usually have to follow the payline rules. Instead of having to line them up on consecutive reels following a win line, you could spin them in any position and they’ll pay!

As always, scatters can act in whatever ways the developer has envisioned. Take the cascading Miner Donkey Trouble slot as an example. The dynamite scatters detonate on the grid to make room for fresh symbols, add two wilds to the grid and trigger the free spins bonus round.

Miner Donkey Trouble screenshot of the feature

In some slots, you’ll also come across jackpot scatter symbols. They are similar to scatters but are frequently used to unlock the game’s jackpot feature. To win a jackpot, you’ll usually need to land a certain number of corresponding symbols within the bonus round, base game or both.

Other Special Symbols

The more you play slots, the more you’ll realise that symbols keep evolving. With every new release, there’s something new to look forward to. Features like sticky symbols, stacked symbols, exploding symbols, and expanding symbols add more depth and excitement to the game.

Gif of stacked symbols slot feature

Stacked Symbols Slot Feature

Colossal symbols are especially amusing in the quirky Visitors release from ELK Studios where the Big O Beam alien expands paying symbols into big sticky 2×2 or 3×3. You can also find symbols as big as King Kong himself in Forgotten Island Megaways.

Forgotten Island Megaways screenshot of the feature

Win Ways

The easiest way to understand a payline is to compare a classic pub slot machine to a modern online game. Pub or fruit slots only had one straight payline or betting line across 3 reels. In modern video slots, you can bet on multiple paylines from 5, 10 and 20 to 50 or even 100. The paylines, also called winning lines, can be anything from horizontal to zigzag, they can also be fixed and flexible and will be clearly displayed in each game’s paytable.

On each spin, the slot machine will use the paylines that you’ve bet on to calculate whether you’ve landed any winning symbols or not. Most modern video slots use fixed paylines meaning that the money you bet covers all possible winning lines. The paylines on most slots pay one way, from left to right. However, you can find slots that pay both ways! On a Win Both Ways slot, winning combinations will pay if they fall on a payline starting from the left and starting from the right!

Gif of win both ways slot feature

Win Both Ways Slot Feature

Just like special symbols, paylines have also evolved with time, and now we have slots with features such as Win All Ways, 243 Ways To Win (same as Win All Ways on a 5×3 slot), Megaways and Cluster Pays, as you can see here in Cluster Slide by Elk.

Cluster Slide slot screenshot of the reels

Reel Features

There’s much more to video slots than just special symbols, regular paylines or ways to win mechanics. Slot reel features like Reel Swap and Locked Reels can boost your winning chances. Many games also have unique interactive features like Reel Hold where you have to manually choose which reel you want to hold in place for the next spin.

Gif of reel hold/reel lock slot feature

Reel Hold Slot Feature

Wild Reels consist solely of wild symbols, hence the feature name, giving you increased chances to form more winning combinations.

Twin Reels or the Reel Sync feature is exceptionally well represented in the popular Twin Spin slot sequel, Twin Spin Megaways from NetEnt. During the game, a set of adjacent reels, up to 5, can be chosen to twin or sync at the start of each spin in the base game or the bonus round increasing your ways to win accordingly.

Twin Spin slot screenshot of the feature

Win Boosters

Another way to win better is to play slots with win boosters. In some slots win boosters such as respins, multipliers, nudge and especially avalanche or tumbling reels can take centre stage.

Respins will give you a second chance to win, while multipliers double, triple or even quadruple your wins depending on the game. When multipliers don’t reset between spins, they can be super lucrative during bonus rounds or mini-games. Nudging reels also give you a second chance to win by introducing a new row of symbols which could help you complete wins.

Gif of nudging reels slot feature

Reel Nudge Slot Feature

The avalanche mechanic, during which winning symbols are removed, and the empty positions are filled with new symbols is particularly popular in many video slots. The reason is that any new wins formed will be added to the existing win on the same spin resulting in possible bigger wins. The epic NetEnt’s Gonzo’s Quest is the perfect example of the Tumbling Reels mechanism.

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Bonus Rounds

In-game bonus rounds are the best part of any slot game. They add an extra dimension to the game and increase your chances of winning even though they don’t cost you anything from your balance. Ultimately, bonus rounds are where the biggest wins happen. In most slots, they can be triggered by landing a required number of scatters or other special bonus symbols in the base game.

Bonus rounds can be classified into two fundamental categories: free spins and bonus games. The in-game free spins bonus round awards a number of free spins that don’t affect your play balance. Depending on the game, you can win 5, 10, 20 or more free spins whenever you trigger a free spins bonus round. Often, you can trigger the bonus round by spinning Scatter or bonus symbols.

Win Free Spins scatter slot feature

Trigger Bonus Round Slot Feature

Some developers like adding additional features that only trigger within this round, like progressive multipliers, jumping wilds, respins and more. In many slots, more free spins can be added, or an entire round can be retriggered to keep the feature going.

The bonus game category includes in-game rounds like Bonus Wheel, Mini-Slot, Pick a Bonus, Jackpot Bonus and many more unique features. These can be triggered in a number of different ways usually specified in the paytable.

You’ll find several more slot features in the below table that can add more excitement to your gameplay and improve your winning potential.

Additional Slot Features

Pick a Bonus This feature allows you to manually select your own bonus.
Mini-Slot Feature This fun feature allows you to play a slot within a slot, in some cases, multiple mini slots.
Bonus Wheel An in-game bonus wheel can award extra free spins, multipliers, instant cash, jackpots or any other feature to boost your bankroll.
Random Features These can be anything from symbol upgrades, extra wild and sticky multiplier features that trigger on a random basis.
Hold and Spin During this feature you collect (usually instant cash) symbols to increase your payouts.
Cluster Pays To win in a grid slot, you need to form clusters of 5 or more identical symbols on the reels.
Retriggering Feature This feature allows you to restart the current bonus round according to the paytable rules.
Wild Overlays Random symbols that have Wild Overlays will operate as wild symbols.

How to Choose the Best Slots with Features

Choosing the best slots is never easy, but there are a few ways that our experts say will help you narrow down the choice and pick games that are worth your while.

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Read the Paytable

We have already mentioned earlier that reading a paytable helps you to get to know the game better. Here you’ll find the rules, symbol payouts, special features and how to trigger them. Browsing the paytable is the quickest way to find out the game’s betting range, max potential, RTP and other key stats to see if it suits your budget and playing style.

Play in Demo Mode

Many casinos allow you to play slots for free before you play for real money, and that’s one of the best ways to get a taste for the game. At the same time, you’ll get familiar with the game’s pace and how often wins hit. Playing in demo mode doesn’t mean that you’re deprived of any special features you get when you play for real. You still get the same experience but without winning real money.

Read Slot Reviews

This is one of the top tips from our casino experts. Here at JohnSlots, we investigate every aspect of a slot and then publish our detailed slot reviews to bring you a thorough and honest summary of its features, potential and payouts. Save yourself a chunk of time by checking out our latest online slot reviews.

Favourite Developer

Casinos rarely create slots, therefore choosing a slot based on your favourite developer is a much better idea. If you like a specific style of graphics, special features and the mechanics that the developer uses, stick to it until you’ve gained confidence and developed a playing style. In the long run, this will make it much easier to choose games that you actually like rather than picking them blindfolded.

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Best Slots With Features

To get you started, our expert team has picked out these 10 fantastic slots from the top developers, all running on different reel mechanics and boasting intriguing features.

Genie Jackpots Wishmaker Scatters, wilds, extra wilds, respins, colossal symbols, symbol transformations, mystery symbols, 6 x bonus rounds.
Reactoonz 2 Multiple wilds, symbol explosions, colossal symbols, win multipliers, avalanche reels, cluster pays mechanic.
The Dog House Megaways Scatters, sticky wilds with multipliers, 2 x free spins bonus rounds.
Mystery Museum Scatters, wilds, stacked symbols, nudge feature, free spins.
Mega Fire Blaze Jackpots: Legacy of the Tiger Wilds, scatters, free spins, respins, win multipliers, fixed jackpots.
Buffalo Power: Hold and Win Wilds, scatters, free spins, win multipliers, bonus game with respins and fixed jackpots.
Pink Elephants 2 Wilds, scatters, free spins, symbol transformations.
Punk Rocker Wilds, jumping wilds, wild transformations, scatters, xWays, free spins, enhancer reel with win multipliers and extra free spins.
Double Stacks Wilds, scatters, double stacked symbols, free spins.
Rich Wilde and the Tome of Madness Special wilds, multiplier wilds, mega wilds, symbol collection, free spins with reel modifiers, clusters pay mechanic.

Genie Jackpots Wishmaker

Genie Jackpots Wishmaker slot review screenshot

This 5-reel and 20 payline slot from Blueprint Gaming is a melting pot of bonus features. Playing Genie Jackpots Wishmaker is like taking a crash-course in slot features.

Wilds here substitute for all paying symbols except scatters, 3 of which award a spin on the Wishmaker’s bonus wheel. Spinning the wheel will grant 1 of 6 bonuses including cash prizes, free spins with progressive multipliers, free spins with multiplier wilds, respins, and two pick bonus games awarding cash prizes and more multipliers. But that’s not all. Look out for golden genie lamps awarding not one but a whole seven reel modifiers. These range from 3×3 colossal symbols, respins with sticky symbols and symbol transformations to mystery symbols and much more.

Reactoonz 2

Reactoonz 2 screenshot of the bonus round

Reactoonz 2 from Play’n GO is another good example of when the developers geek out on bonus features. This is not your ordinary reel slot, but a 7×7 grid game featuring some charge-hungry alien critters, four wilds, multi-level meters, multipliers, symbol explosions and colossal symbols. Wins here can be achieved by getting 5 or more symbols in clusters which are removed for new symbols to fill in the gaps. It looks and sounds intimidating for any new player, but the trick is in the cascading reels, leading to non-stop consecutive spins and, eventually, to big wins.

The Dog House Megaways

The Dog House Megaways screenshot

Slightly less unhinged but nonetheless a very fetching release from Pragmatic Play, The Dog House Megaways will teach you a trick or two about some exciting slot features. Headlining the famous Megaways mechanic and an expanded 7×6 reel set-up, it offers up to 117,649 different ways to win and several intriguing bonus features. Wilds carry multipliers, but it’s the free spins round where the juiciest treats are hidden.

Mystery Museum

Mystery Museum slot screenshot

With a name like Mystery Museum, you’re sure to embark on some intriguing gameplay. It starts with Mystery Stacks or special symbols that land in stacks and nudge up to fill the reels when 3 of them land in view. Spying on you with his glowing eyes is Samurai, the game’s wild and scatter symbol. Landing 3 of them will open up the bonus round where mystery stacks expand and stick to the reels for the bonus round duration only to grant you some enigmatic wins.

Mega Fire Blaze Jackpots: Legacy of the Tiger

Legacy of the Tiger slot screenshot

The Mega Fire Blaze Jackpots: Legacy of the Tiger slot sounds like a mouthful, but there’s nothing too complicated here in terms of gameplay. You only have two major bonus features to look out for, the free spins round with a special reel and a multi-tiered Fire Blaze jackpot. Your goal is to trigger the free spins game with 3 tiger scatters or the jackpot session with 6 or more moon bonus symbols. The jackpot game consists of 9 lines in total and every two moon symbols with a key on it unlocks 2 extra lines. Reach the top 9th line to win a jackpot.

Buffalo Power: Hold and Win

Buffalo Power: Hold and Win slot screenshot

Hold and Win slots are fun to play, but Buffalo Power is a particularly thrilling one for its intriguing bonus features. The free spins round kicks off with 8 free spins with active multipliers, but if you spin 6 bonus symbols into view, the Hold and Win feature triggers. That’s when things start getting interesting. You get 3 respins where only bonus symbols land and stay sticky on the reels. If you collect 5 power symbols, you win the Mega jackpot!

Pink Elephants 2

Pink Elephants 2 video slot

Cute name, fierce gameplay! Pink Elephants 2 is a surreal 4,096 ways to win slot and a successor of the original game with the same name from Thunderkick. It comes with mystery scatters and a free spins bonus game containing symbol upgrades and retriggers. Filling up four meters with Elephant orbs and transforming symbols into the highest-paying Pink Elephant symbols in the process could land you wins as big as 10,000x your bet.

Punk Rocker

Punk Rocker Slot Screenshot

If noisy rock tunes combined with unapologetically risky gameplay sounds like something you’d enjoy, then try Punk Rocker from Nolimit City. Besides having all the cool features like respins, multipliers and jumping wilds, the xWays expanding reels will give you up to 46,656 win ways during the bonus round. It’s highly volatile but worth giving it a go for its rock-n-roll 15,072x your bet max win.

Double Stacks

The twist is in the name. This classic fruit-bursting Double Stacks release from NetEnt is a juicy little number that pays double for any stacked symbols on its 5 reels. Whenever a reel stops spinning and contains one type of symbol, every symbol on that reel will be counted as two symbols. Better yet, in the free spins round, wilds also land stacked, helping to boost your winnings further.

Rich Wilde and the Tome of Madness

Rich Wilde and the Tome of Madness video slot from Play N Go

If you haven’t yet, follow in Wilde’s adventurous footsteps to uncover secrets of the sinister Cult of Cthulhu in Rich Wilde and the Tome of Madness. This is another feature-rich slot from Play’n GO boasting cascading 5×5 reels, free spins with multiple reel modifiers, symbol collection and an army of wilds with special powers.

Best Slot Game Developers That Are Known for Their Features

Knowing your game developers is key in choosing the best slots to play, so we’ve listed three of the industry-leading software providers that never cease to surprise us.

Big Time Gaming

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Best known as the developer of Megaways mechanics, BTG is the world’s leading supplier of high-quality slot games. They know exactly what the player wants and they go for it. As a result, you can enjoy features like an Unlimited Multiplier as well as the Dual Reaction mechanism. Their slots like Bonanza Megaways, White Rabbit Megaways and Danger High Voltage are played worldwide for their innovative and unique features.


Top 5 Yggdrasil slots

Yggdrasil, meaning a tree of life in the Norse mythology, have been delivering an epic gaming experience since 2012. They are continually delivering high-performance slots with beautiful artwork and innovative features. Some of the most notable include the Splitz mechanic that gives a game an exhilarating boost and the popular PopWins mechanic where a winning symbol is replaced with two as it ‘pops.’

High 5 Games

High 5 Games logo on purple background with 2 fairy characters

Producers of numerous top-performing slots for IGT, High 5 Games deserve a special mention for their distinctive innovations. The most recognisable features include Tumbling Reels, Super Symbols, Split Symbols and Super Stacks which add a world of difference to any slot machine in the way it looks, feels and operates. Founded in 1995, the developers have grown into a full-fledged independent slots provider celebrated for its iconic Da Vinci Diamonds and Golden Knight slot releases.

Where to Play Slots with the Best Features

If you’re looking for a safe and sound place to play slots with the best features, stick with JohnSlots. The list below features the best online casinos for slots that have passed our rigorous rating criteria set by our casino experts. Our ratings cover key areas like games collection, bonuses, banking and special features.

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Play the Best Slot Games with Features at

Slot features make a thrilling addition to any slot game. They boost your win potential and make the game you play more engaging. Now that you know what features are and how they work, why not explore our extensive list of new slots and most popular slots for picking yourself a game and applying theory into practice. Or you can always try something different and learn more about hybrid slots in our detailed Slingo page.


Ready to spin but have more questions about features? Check out the answers to the most frequently asked questions by slot players below.

Slot Features FAQs image on green background

Not exactly. Slot features are the key symbols and bonuses you see on the screen like Wilds and other special symbols, avalanching reels, Megaways win ways and bonus rounds. On the other hand, slot mechanics are the behind-the-screen features that determine the outcome of your spin and indicate the game’s potential. These include the Random Number Generator (RNG) mechanism, return to player (RTP) percentage and the volatility rate.

This depends on what types of features are included in the game. If the game contains special symbols like wilds, then they can improve your winning combinations by substituting for other symbols. Scatters or bonus symbols are capable of triggering different bonus rounds, during which you can win more free spins to boost your winning chances. Features can also unlock things like jackpots, unlimited progressive multipliers, extra free spins and much more.

The best features are those that help you trigger bonus rounds and increase your win potential, such as win multipliers that don’t reset between spins. Avalanche or tumbling reels, for example, can bring you multiple wins on a single spin. Scatters are always good to have as well. In theory, there is no one best feature, each and every one of them is programmed to work together, and you should always keep in mind that they might not always bring you wins.

This largely depends on your budget and your playing style. If you love fast-paced, complex gameplay, you’ll want to go for slots with lots of intricate features and several bonus rounds. These, however, often come with medium-high volatility so you’ll have to mind your budget. But if the volatility matches the max win potential, winning big can be possible. If you’re after a laid back game, then classic, less feature-heavy games, with one bonus round will be better suited.

Some have more than others, but pretty much all slots have features. The classic fruit slots might only have one special symbol such as wild or scatter, but they rarely have bonus rounds. Modern video slots will almost always have a wild and a scatter and at least one bonus game. They’ll also have different reel setups like tumbling reels, infinity reels or a clusters pay grid.

The easiest way to understand the features added to the slot is to check the game’s paytable. Every slot has a paytable where you’ll be able to study symbol payouts, special symbols, bonus rounds and how to trigger them. A paytable will always include key statistics such as the game’s max win, the RTP and volatility and visually display active paylines across the reels. Reading the paytable before playing will help you understand what’s happening on the reels, especially in fast-paced and feature-rich games.

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Online Slot Expert

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Leanna Madden is an expert in online slots, specializing in analyzing game providers and evaluating the quality and variety of slot games. With her extensive knowledge, she guides players to the best slot options, including high RTP slots and those with exciting bonus features. Leanna's insights help players make informed decisions and enjoy rewarding slot experiences at online casinos.

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