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Most Popular Online Slot Features Explained

Round Head IconNovember 29, 2018 - CasinoBloke

Remember the days when placing the bet and pulling the lever was pretty much the whole shebang when it comes to slots? Fortunately, the playing field has since changed drastically, and new slots are not only visually stunning but also packed with bonus features that can sometimes blow your mind. The VR technology has pushed the bar even further and we can’t wait for the day when all of these amazing features will finally be available in virtual reality.

While we are waiting for our favourite releases to be re-designed and available in VR form, let us revisit some of the most popular features that lifted video slots to an entirely different level. For some extra clarity (and to make sure we don’t forget any), we will start by dividing them into the following categories:

  • Free Spins
  • Re-spins
  • Wilds 
  • Multipliers
  • Bonus Games
  • Gamble Feature
  • Cascading Reels 
  • Nudge Feature
  • Collectible icons 
  • Extra Reels
  • Meter
  • Megaways

A lot of these features can have multiple versions and you can often find them co-existing, depending on the developer’s willingness to experiment. 

A lot of these features can have multiple versions and you can often find them co-existing, depending on the developer’s willingness to experiment.

Free Spins

Obviously, Free Spins have become an indispensable part of video slot bonus features, and you will have a hard time finding a game that does not include this type of incentive. This is a pretty self-explanatory feature, usually triggered by the combination of the Scatter icons and initiating a certain number of rounds at the same betting level as the triggering spin.

The number of spins can either be fixed or conditioned by the number of Scatters within the combination. In other words, the more Scatter icons land on the reels, the more bonus rounds will be unlocked.

Re-triggerable Free Spins

In some cases, Free Spins can be reset when the triggering icons land on the reel while the feature is still in progress. More spins will be added on top of the original session and some developers will apply no limitations to the number of rounds that can be unlocked, which means that you can (theoretically) win hundreds of continuous spins for the price of one.

Free Spins with multipliers

Sometimes, all wins generated during the bonus round will be doubled or tripled. These are technically not actual multipliers, but fixed amounts applied to the payouts won in the bonus rounds.

Where can I find this feature?

Gunslinger: Reloaded by Play’n GO doubles all the wins during the Free Spins, which can be triggered over and over again!


People often mistake Free Spins with Re-spins, although these are two different features.
The players will usually start the feature with only 1-3 Re-spins which are played on the free reels, while the reel that triggered the Re-spin remains locked. Sometimes, a relevant symbol can add an extra Re-spin on one of the free reels, increasing the winning chance.

Where can I find this feature?

Play’n GO is particularly fond of Re-spins, and Sizzling Spins, Hugo Goal, and Golden Colts are some of the titles where this bonus can be found.


These icons can come in many different forms and even cover an entire reel, turning it into yet another great bonus feature called the Wild Reel. The Wild symbol can be described as the Wild Card, which can replace any other card (or symbol, in this case) to form a winning combination. 

Another advantage of Wilds is their high payout value and the fact they can sometimes increase the value of any combination they complete. Scatters – the icons that can both trigger the bonuses and generate payouts – are the only symbols that cannot be replaced by Wilds.

Slots can either have one or multiple Wilds (represented by the featuring icon of the game) or no Wild icons at all. In Ozwin’s Jackpots slot the lack of Wilds in compensated by 5 progressive jackpots.

Some of the most popular forms of Wilds are:

  • Expanding/Stacked Wild – expands across multiple reel positions 
  • Sticky Wild – sticks to the landing positions
  • Roaming/Walking/Jumping/Rolling Wild – moves across the reels, finding a better position
  • Colossal Wild – covers multiple positions as a single, colossal symbol
  • Replicating Wild – replicates upon landing
  • Random Wild – randomly selected icon that becomes Wild during bonus rounds
  • Linked Wilds – transform all other icons between them into Wilds
  • Multiplier Wild – increase the payout
  • Mystery Wild – a universal icon that can turn into any other symbol

Where can I find this feature?

Jump! by Habanero (Sticky + Jumping Wild)

Danger High Voltage by Big Time Gaming (Sticky Wild)

Dwarfs Gone Wild by Quickspin (Rolling Wilds, Spreading Wilds, Throwback Wilds, Full Reel Wilds, and Free Wilds).

Wild Bazaar by NetEnt (Colossal Wilds, Linked Wilds, Multiplier Wilds, and Stacked Wilds)

Baron Samedi by Yggdrasil – (Mystery icon that only appears in the Free Spins and Re-spins, turning into a random symbol).


Multipliers can be progressive or fixed, and they can be awarded in the bonus rounds, or on a Wheel of Fortune. Some slots feature progressive multipliers which increase on every single spin that does not generate a payout.

Where can I find this feature?

Where else than in one of the most popular slots of all times, Gonzo’s Quest by NetEnt.

Pick Me Bonus Games

This usually refers to Pick Me games, where the players are offered with multiple choices, each hiding a cash prize. Depending on the slot, the players will get to select one option or continue to pick until an empty field is revealed. Variations exist, and the players can also choose between different paths, opening presents (Christmas releases), memory games…

Where can I find this feature?

Wild Swarm by Big Time Gaming, where the players can pick between five Hives for an instant cash prize.

Gamble Feature

A risky, yet highly popular option that allows you to double, triple, or quadruple your winning, usually by flipping a coin, or guessing the card colour.

Where can I find this feature?

Microgaming is really keen on Gamble Feature and if you would like to play for double or nothing, try their Empress of The Jade Sword.

Cascading Reels

Regular reels can become Cascading reels after a win, boosting the player’s winning odds. Instead of spinning, the symbols will fall down and explode after forming a winning combination, making room for new falling icons.

Where can I find this feature?

Jammin’ Jars by Push Gaming will activate the cascading reel as soon as a cluster of at least five icons is formed on the grid.

Wheel of Fortune

Another popular online slot feature, prompting the players to spin the wheel and win a multiplier, free spins or a cash prize. Usually, the prize is guaranteed. 

Where can I find this feature?

Halloween Slot by Microgaming; the players can land on a multiplier or on a slot symbol that unlocks a bonus.

Nudge Feature

Sometimes, the symbols needed for a winning combination land on the reels, but not in the right positions. When that happens, the slot can award the players with a little bit of a nudge, that will shuffle the icons and position them where they can complete the winning combo.

Where can I find this feature?

Hanzo’s Dojo by Yggdrasil introduces the 3×3 icon that can move up to 3 reel spaces from its original position.


Collectibles are an ongoing feature, adding a certain symbol to the player’s collection until a pre-determined number is reached. When that happens, a bonus feature is triggered.

Where can I find this feature?

Fat Rabbit by Push Gaming, with the carrots as the collectibles. The more our bunny eats, the larger he will become and when the Carrot Meter is completely full, the Rabbit will expand (Growing Wild) and activate Free Spins.

Wild Swarm by BTG with collectible bees.

Extra and Extending Reels

Some slots start off as typical 5-reel games, however, additional reels can be unlocked. The extra column can be located at the top or at the bottom of the screen (horizontally), or appear as an extension of the existing reel, adding more symbols in the vertical column.

Where can I find this feature?

Sidewinder by Microgaming with top and bottom horizontal reels and White Rabbit by Big Time Gaming with Expanding reels. 


Similar to collectibles, a meter allows you to store certain icons or powers, and then unleash them when the storage is full.

Where can I find this feature?

Reel Talent by Microgaming with the meter placed on the side, to the left, storing the icons and unlocking one of the three Superspins: Showtime, Big Stage, and Solo Performance.


Patented by Big Time Gaming, Megaways system is now being applied by other developers as well. Slots with the Megaways pattern randomly change the number of paylines on every spin.

Where can I find this feature?

Bonanza, White Rabbit, or Extra Chilli by BTG.

If you are looking for the most reputable online casinos where you can enjoy most slot games mentioned above, Casino Bloke can highly recommend the likes of LeoVegas, Bitstarz and 7Bit Casino.

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