By Alex Smith Feb 29, 2024

Thunderstruck II Review

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Themed around ancient Norse Gods and packed full of action, Thunderstruck II is one of Microgaming’s most iconic releases in history. It’s a true pioneer of the Norse mythology slots, which, today, are everywhere in the online gambling world.

Thunderstruck II is famed for its exciting Wild Storm base game feature and the free spins round where you get to choose one of four different bonuses. In this Thunderstruck II slot review, we’re going to be looking at the slot closely, seeing what makes it such a popular choice with players.

Paylines243 ways
Reels5-reel, 3-row
Min Bet0.30
Max Bet15

Which Online Casinos Play Thunderstruck II?

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Thunderstruck, the prequel to Thunderstruck II, was one of Microgaming’s very early releases, and while it lacked today’s HTML5 technology, it proved popular among players.

The game offered decent win potential and was built around a volatile math model, something many players look for.

In 2010, at the London iGaming conference (ICE), Microgaming attracted widespread attention after announcing they’d be developing a sequel to Thunderstruck. The result, Thunderstruck II, quickly transformed into one of the developer’s most successful slots ever made.

Originally developed using Flash technology, Thunderstruck 2 is now available at all online casinos in HTML5, so it plays more smoothly and is also fully mobile-optimized. It’s not the most graphically impressive video slot in the world. Still, the creative free spins feature, the base game modifier and the soundtrack all fit together incredibly well — and you can win upwards of 8,000X your stake while playing!

In terms of design, Thunderstruck 2 is built around a 5-reel, 3-row format. Instead of paylines, it uses a ‘243 ways to win’ format, so winning combinations are formed by landing three or more symbols on adjacent reels from left to right.

How To Play Thunderstruck II

Thanks to the “HTML5 facelift” Thunderstruck 2 received, it’s not a lot easier to play the game than it used to be, and you don’t have to faff around with “expert mode” and complex coin values.

As with all online slots, the first thing you’ll need to do is select the amount of money you’d like to wager on each spin. Thunderstruck 2 allows you to bet from as little as $0.30 and as much as $15 per spin, so the low maximum bet should already be a dead giveaway that this game has some pretty serious win potential.

Depending on which version of the game you’re playing, you may or may not have autoplay available to you. For some reason (likely due to regulatory concerns), many of Microgaming’s early HTML5 conversions were shipped without autoplay. Although, they have started to offer it again in some titles.

If autoplay is available, you’ll be able to set up to 100 spins to play out automatically, removing the need for you to press each spin manually.

Similar to the autoplay function, some versions of Thunderstruck 2 may also offer a quickspin mode. However, this appears to be relatively rare, especially since regulators like the UK Gambling Commission have outlawed faster-spinning slots. Still, if it is available, you’ll be able to play the game at a much faster rate, virtually doubling the number of spins you’re able to get through each hour.

RTP and Volatility

Contrary to what many new players think — and unlike the original version of the slot — Thunderstruck II is classed as a low variance slot. This may come as a surprise even to experienced slot fanatics, given the potential within the game. But Microgaming itself has confirmed the math model is low variance.

RTP-wise, Thunderstruck II is pretty decent too. The fixed RTP is 96.65% higher than most casino games we see released today and, twinned with the low volatility math model, makes for interesting gameplay.

Symbols and Payouts

Microgaming’s Thunderstruck II slot offers a variety of symbols, all with differing payouts, and the low-value ones are represented by playing card values.

This includes 9, 10, J, Q, K and A. These aren’t worth a huge amount. Still, as with most 243 ways to win slots, big wins are possible if they’re stacked enough across the five reels.

Thankfully, the slot’s premium symbols are much better paying. They include a Ship, Valkyrie, Loki, Odin and Thor. These premium symbols are worth up to 16X your stake for matching a 5-of-a-kind combo. While that may not sound like much, you’ve got to remember that all of them — Loki, Odin and Thor — can appear in multiple positions on a single reel, allowing you to form multiple “ways” of each symbol.

There’s also a wild symbol in the Thunderstruck II slot; the game’s logo is the wild. This substitutes for all symbols (aside from the scatter, Thor’s Hammer), and when the wild forms part of a win, it multiplies the total win amount by 2X.

Bonuses and Features

So far in this review, we’ve talked exclusively about Thunderstruck II’s mechanics and some of the nitty-gritty of playing and how payouts work.

What we haven’t yet covered is the hugely exciting bonus rounds, all of which are capable of producing significant wins. There’s a random bonus feature (which can award the slot’s max win) and four free spins features, and below we’ll look at all of these bonuses in-depth.

Wildstorm Feature

The first of the bonus features you’ll find inside Thunderstruck II is actually one that triggers randomly within the base game. It’s called the Wildstorm feature.

You’ll know when the Wildstorm feature is triggered because the reels don’t stop spinning, and you’ll see bolts of lightning striking the reels. You’ll then see Thor jump magnificently onto the reels, transforming reels into wild reels.

It’s possible for the Wildstorm feature to transform all five reels into wilds. To do so awards you the game’s max win — a whopping 8,100X your stake.

While this bonus doesn’t appear too often, you’re usually always guaranteed some kind of win when it does. If you manage to get three or more of the reels transformed into wilds, you could well find yourself walking away with a mega payout.

Introducing The Great Hall of Spins Feature

The main bonus in the Thunderstruck II slot is known as The Great Hall of Spins Feature. This feature is triggered by landing three, four or five of the scatter symbols anywhere in view.

New players will find themselves being automatically awarded one of the four free spins features. Still, as you play the game more, you’ll eventually get to pick which free spins options you want — and The Great Hall of Spins feature offers a ton of variety.

In fact, despite not offering quite as much win potential as the Wild Storm feature, it’s the Great Hall of Spins bonus that attracts new players (and existing slot fanatics) to the game. Let’s take a look at the different free spins features below:

Valkyrie Free Spins

The Valkyrie free spins bonus is the first of the four free spins you’ll be awarded, and you’ll see yourself awarded ten free spins. During this free spin bonus, all wins you manage to form are multiplied by 5X. When wins are formed using a wild symbol, the multiplier increases to 10X. So, landing a full line of Valkyrie, Loki, Odin, or Thor will result in a massive win.

In this free spin bonus, it’s also possible to retrigger the feature. To do so, you need to land another three, four or five scatter symbols anywhere in view. Doing so will award you ten additional free spins.

Loki Free Spins

Thunderstruck II’s second free spins feature is the Loki free spins bonus, which sees you awarded 15 free spins. During these spins, the Wild Magic Feature also becomes active.

The Wild Magic Feature means that a special symbol is placed onto the third reel, a Wild Magic symbol. When this lands in view, it randomly transforms symbols on the reels into wilds. You can, potentially, get a full screen of random wild symbols added if you’re lucky!

Odin Free Spins

The Odin Free Spins Bonus is the third free spins feature in Thunderstruck 2, and when triggered, you’ll be awarded 20 free spins. The bonus game will then begin to play out, but a new modifier called the Wild Raven feature will be activated.

For the duration of the bonus, you’ll notice that two Ravens fly above the reels. Randomly, on any of the 20 free spins, they can fly onto the reels and turn symbols into 2X or 3X multipliers.

The Wild Raven Feature is one of the better bonus game mechanics in Thunderstruck 2. We like the way it can randomly turn symbols into multiplier wilds; your goal will be to increase the multiplier by landing multiple wild symbols on the same spin.

Thor Free Spins

The Thor Free Spins bonus is perhaps the second-most favoured bonus within Thunderstruck II, after the Valkyrie Free Spins. That’s because it uses a Rolling Reels feature in the bonus game. Once activated, you’ll be awarded 25 free spins, and these free spins with rolling reels mean that any symbols that form a win during the bonus disappear, with new ones dropping down to take their place.

The Rolling Reels mechanic means the bonus can go on for quite some time. Each consecutive time wins are formed, the multiplier also increases, up to a maximum of 5X. This multiplier then stays resets per spin.

Thunderstruck 2 is famed for its free spins feature bonus. If you’re looking to play Thunderstruck II for yourself, you may be wondering which bonus you should choose?

In all honesty, it’s up to you, but the majority of players choose the Valkyrie spins feature as it’s the most volatile of the bonus options. The free spin bonus can also be retriggered an unlimited number of times.

Our verdict

Regardless of which free spin option you choose, the bonus spins in Thunderstruck 2 are known for offering great win potential. Both new players and experienced slot players will find themselves able to enjoy the chance of hitting massive wins while playing a low variance slot — a pretty unique situation.

In our opinion, it’s always worth choosing the Valkyrie bonus spins option; this, we feel, is the feature with the most potential. Thanks to the fact that you can retrigger the bonus spins, the bonus can carry on for quite some time.

Thunderstruck II’s bonus action makes for really interesting gameplay, and we love how Microgaming has displayed the Norse mythology theme throughout. While there are definitely better-looking Norse mythology slots on the market today, Thunderstruck 2 is iconic and seen by many as the “original” game to play. With so much potential in both the base bonus round and the free spins feature bonus, it’s easy to see why the slot’s become one of the software provider’s most popular releases to date.

While the max bet is pretty low (just $15), Thunderstruck II is accessible to players on all budgets. Both new players and experienced players will be able to enjoy the action of the game at a stake that suits them.

On the whole, Thunderstruck 2 is a fantastic release from Microgaming, and it’s a great sequel to the original Thunderstruck game. The slot, with characters like Thor, Odin, Loki and other Nordic icons, looks great, and the slot game is well worth checking out if you’re looking to try an old-school classic!

Thunderstruck II Review FAQs

The main bonus spins feature in Thunderstruck 2 is triggered by landing three or more of the scatter symbols anywhere in view on the five reels; you can land five max, and doing so will award you entry to the main bonus round.

Here, you’ll be able to choose one of four different free spins features. Unlike other slots like Book of Dead, you can choose the number of bonus spins you want, with each option offering a number of different reel modifiers!

The max bet while playing Thunderstruck 2 is pretty low; Microgaming has chosen to implement a max bet of just $15, and this should give you some indication of the kind of win potential the slot offers.

The low max bet may turn away some of the higher-staking players. However, those who deposit small amounts of money — and want to low roll on the game — will have no issues as the minimum bet is just $0.30.

While the answer to this question changes depending on which casino where you’re playing and how much you deposit. Generally speaking, you won’t have any issues playing the slot with a welcome bonus.

Be aware that if you do claim a bonus, you’re likely to have a $5 max bet limit. There will also be wagering requirements attached to the deposit bonus. So, while it may be one of the best slots ever released, you probably will need to hit multiple combos of symbols across all five reels — or get lucky in the bonus spins or the wild reels feature — to get your balance high enough to clear the deposit bonus requirements!

If you do choose to claim a deposit bonus, make sure to read the terms and conditions. Deposit bonus offers often have several other terms attached, and you’d do well to familiarise yourself with these terms before playing.

Alex Smith

Alex is a 26-year-old writer from Brighton, in the UK, and for the past 8 years, he’s worked with a number of companies, creating content for blogs, news articles, and more. While Alex has written on a wide variety of topics, his speciality is online gambling – an industry he’s both passionate about, and experienced in. Having enjoyed gambling for over 7 years, Alex is a huge fan of video slots, and cites NetEnt, Big Time Gaming, Thunderkick, and Quickspin as his favourite providers. The topics he writes on are varied, but he loves nothing more than a good old slot review (he’s written over 1,000 slot reviews in his career), and he also enjoys writing in-depth gambling guides, along with casino reviews. In his spare time, Alex enjoys playing the guitar, and is a self-proclaimed horror film buff.

Paylines243 ways
Reels5-reel, 3-row
Min Bet0.30
Max Bet15