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Doctor Electro slot review

Added by Kalamba Games. Information last updated: 07/04/2021

User rating:

- (0)

Expert rating:

3.5 (1)

Game information

Game supplier: Kalamba Games

Release date:05/2019



Max. win:bet x 2000

Mobile version:Support all devices

Play Doctor Electro




Expanding reels

Bonus game or special game





User ratings (0)

Game design:



Game sounds:

Mobile gaming:



Screenshot Screenshot Screenshot
RTP (Return to player):
Max. win:
bet x 2000

Bojoko score (compared to other slots on Bojoko)
Kalamba Games score (compared to other slots of supplier)

Expert's review Trystan Michielsen

Slot tested

Doctor Electro shows us the life of an eccentric professor who spends his time dealing with electricity in order to perform experiments. This game further features expanding reels, 2 jackpots and free spins to keep the players entertained.

Released in 2019, this Kalamba Games strives to bring us into the world of cutting-edge technology and strange experiments as we watch this doctor at work. The game is built around a 5-reel, 4-row playing field that has an additional 3 rows it can unlock. Behind the reels, we can see his laboratory, involving him standing on a floating platform as well as a plethora of machines and devices.

The game looks quite good and there are some subtle animations that help bring the character and his lab to life. The man himself is seen standing on the left side of the playing field, moving organically when nothing is happening but also celebrating when there’s a win or activating the features. We can also see different coils and cables sizzle with electricity as the game goes along.

On the playing field itself, there is some movement as well. The game can expand the reels by sending electric pulses through them which is animated. Some of the symbols themselves also move on their own, usually showing off different electrical effects. It all fits the theme quite well and it brings the whole game to life.


Doctor Electro features a standard collection of low- and high-paying symbols. Card letters are used to fill up the low-paying symbols, which unfortunately do very little in terms of adding to the setting. The high-paying symbols consist mostly of different characters that we might find in the doctor’s laboratory, but it’s never really made clear who they are or what their purpose is. These symbols also aren’t animated whenever they’re part of a win.

Speaking of wins, the game has a total of 1,024 paylines during the base game which can increase to 16,807 paylines when the playing field has grown to its maximum size. Despite this, the slot has High Volatility, mostly because you won’t have the playing field at its maximum size very often. There are also a lot of different symbols and those do not pay out huge amounts when part of a win.

Players can deal with the volatility by having their bets adjusted. This can be done through the menu and allows players to pick a bet between £0.30 and £45 per spin. As a result, it can be easier to get a bigger win or it will take longer to lose a significant amount of coins, depending on the choices the players made.

The game features a wide variety of symbols, including:

  • Bonus: Gather 3 Bonus symbols on the screen at the same time to activate the free spins mode.
  • Wild: Wilds substitute the regular symbols in the game. The Wild plus the Doctor Electro symbol together will trigger the jackpot.
  • Doctor Electro: Max. 4x your bet with five-of-a-kind on a winning bet line.
  • Ethereal Being: Max. 3x your bet with five-of-a-kind on a winning bet line.
  • Researcher: Max. 3x your bet with five-of-a-kind on a winning bet line.
  • Ape: Max. 2.4x your bet with five-of-a-kind on a winning bet line.
  • Robot: Max. 2.4x your bet with five-of-a-kind on a winning bet line.
  • Ace: Max. 1.6x your bet with five-of-a-kind on a winning bet line.
  • King: Max. 1.6x your bet with five-of-a-kind on a winning bet line.
  • Queen: Max. 1.6x your bet with five-of-a-kind on a winning bet line.
  • Jack: Max. 1.6x your bet with five-of-a-kind on a winning bet line.
  • 10: Max. 1.6x your bet with five-of-a-kind on a winning bet line.
  • 9: Max. 1.6x your bet with five-of-a-kind on a winning bet line.


Doctor Electro boasts a selection of features that will augment or enhance the gameplay of this slot. Most of it has to do with the expanding reels, but there are also a jackpot and free spins players can win coins with.

  • Expanding Reels: The game’s 5 reels start off with 4 rows but can grow to be 7 rows high. Tiles are unlocked when an Expansion symbol appears on the reel and the appropriate number of Expansions have been used.
  • 1,024 Ways To Win: Wins are calculated by tracking a symbol appearing on consecutive reels from left to right.
  • Hyper Bonus: The player can choose to trigger the hyperspins mode manually by paying a coin sum, selecting the number of free spins they want to trigger. Getting 3 Expansion Symbols on the screen will automatically trigger the hyperspins mode.
  • Free Spins: Triggering the free spins mode is done by collecting 3 Bonus symbols on the screen at the same time.
  • Multiplier: During the free spins mode, all wins have a 2x multiplier.
  • Jackpot: When the player has enough Wild and Doctor Electro symbols on the screen, this will trigger 1 of the 2 jackpots. With 12 symbols it will award the Gold jackpot, with 14 symbols the Platinum jackpot.

The game’s focus on the expanding reels should be obvious to anyone playing the game for a limited amount of time. The goal here is to get Expanding symbols on the screen one at a time which will help unlock the different tiles above the playing field. Once the hyperspin mode is triggered, by getting 3 Expansion Symbols on the screen, all the tiles that were unlocked will open up and increase the total number of paylines on which to win.

In my experience, the base game won’t offer too many opportunities to get big wins but activating the Hyperspin or Free Spins mode will make it more likely that bigger wins are hit. The opportunity to activate the Hyperspins manually is an attractive option but does cost a hefty amount of coins.

In Conclusion

Doctor Electro is a slot that does a good job at using its appearance to tell a story. Even though there is little information given about the nature of the character, his crew or his experiments, the player will develop their own little narrative as they play.

The gameplay is nice albeit maybe a bit excessive. There are a lot of different features at play here and especially the Hyperspin and Free Spin features resemble each other a lot. The player will do well taking a glance at the paytable to make sure they understand how it works.

If you’re looking for a fun slot that will reward you with the occasional bigger win, I would recommend this game. The option to activate the special feature at will might also be an interesting thing for power players.

Overall rating:


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  • Features

    Wins and bets

    RTP (Return to Player):96.23%


    Max. win:bet x 2000

    Min. bet:£0.3

    Max. bet:£45

    Progressive jackpot:

    Reels & playlines



    Non-standard layout:

    Max. lines:16807

    Min. lines:1024

    Win both ways:

    Other features


    Expanding reels:

    Stacked symbols:

    Colossal symbols

    Auto play:

    Turbo play:

    Quick play:

    Virtual reality:

    Bonus features

    Bonus game:

    Random bonus:

    Progressive bonus:

    Buy bonus:

    Free spins:

    Scatter symbols:

    Bonus game symbols:


    Standard wilds:

    Sticky wilds:

    Walking wilds:

    Stacked wilds:

    Random wilds:

    Multiplier wilds:



    Walking re-spins:

    Sticky re-spins:

    Cascading reels:

    Sticky wins:


    You can play Doctor Electro in English, Finnish, Swedish, German and 9 other languages.

    All supported languages:
    English, Finnish, Swedish, German, French, Spanish, Italian, Russian, Czech, Danish, Norwegian, Portuguese


    Doctor Electro supports GBP, EUR, SEK, NOK and 8 other currencies.

    All supported currencies:
    GBP (£), EUR (€), SEK (kr), NOK (kr), DKK (kr), RUB (₽), USD ($), NZD ($), CAD (C$), AUD ($), mBTC (m฿)


    Release date 05/2019
    12th newest on Kalamba Games 507th newest on Bojoko
    RTP 96.23% 0.19% > average
    10th highest on Kalamba Games 527th highest on Bojoko
    Win up to 2000 x your bet
    12th highest on Kalamba Games 758th highest on Bojoko
    Paylines 16807 83935% > average
    The highest on Kalamba Games 75th highest on Bojoko
    Min bet £0.3 per spin
    2nd lowest on Kalamba Games 1,123rd lowest on Bojoko
    Max bet £45 per spin
    12th highest on Kalamba Games 980th highest on Bojoko
    Rated 0 by 0 members
    The most rated on Kalamba Games 38th most rated on Bojoko
    12 more slots listed by Kalamba Games

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    Expert's profile


    Trystan Michielsen

    Trystan Michielsen

    Trystan Michielsen is a Dutch native who started his career as a content writer for various small businesses who were interested in creating an online presence.

    When the opportunity arose to move to Malta and work in the iGaming sector, Trystan didn't hesitate to make the plunge. Here he worked as a Content and SEO specialist for different companies before moving back home.

    Now acting as a freelancer he maintains his connection with the online slot community by playing and reviewing the wide variety of videoslots that are released.

    Trystan enjoys playing the slots that offer a full experience, focusing on more than just the technical details but keeping an eye on its presentation. Graphics, music and style can create a game that's more than the sum of its parts.

    A writer at heart, putting thoughts to paper is something he's done for as long as he remembers. In his free time, he enjoys writing fiction as well as watching and reviewing movies.

    Latest reviews:
    Doctor Electro cover

    Game supplier:Kalamba Games

    Release date:05/2019

    RTP (Return to player):96.23%

    Max. win:bet x 2000

    Mobile version:Yes

    User rating: 0
    Expert rating: 3.5

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