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Who Wants to be a Millionaire Mystery Box Slot Review

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Who Wants to be a Millionaire Mystery Box Slot is a Big Time Gaming slot launched in 2019. The game houses 5 reels and 243 paylines with a 96.36% RTP. This non-progressive slot game also features multipliers, mobile, scatter symbols, wilds, bonus games, free spins. This game has a jackpot of 12,000x bet and is available for playing on both desktop & mobile.



After a huge success of the original Who Wants to be a Millionaire video slot, Big Time Gaming decided that it was time for a sequel, so the Millionaire Mystery Box was released. The newest BTG title is somewhat similar to its predecessor, but there are some significant differences. The 2019 release features five reels, three rows and benefits from 243 ways to win. Also, the maximum payout is set at 12,000x, instead of 50,000 times the bet, which is the max in the original. We also have the 2x Wild and the Mystery Box, which reveals random symbols when landed. The Free Spins feature is a bit different, with up to 7 freebies at the beginning, and the possible multiplier of up to 50x.

who wants to be a millionaire mystery box Media Gallery


Visually speaking, everything remained the same. The reels are set in the original Millionaire studio, with the same symbols appearing on the reels. Four different Gemstones, including Diamond, Ruby, Emerald and Sapphire, act as high-paying icons, while simple playing cards represent the low-value ones. The Wild substitutes for all regular symbols, appears only on reels 2, 3, and 4, and also comes with a 2x multiplier applied on all wins when the Wild is a part of the winning combo. The Millionaire Logo is the Scatter that triggers the Free Spins feature.

When talking about the rules of the game, there are some differences, comparing to the original video slot. The 2019 release features a standard 5×3 reel grid and benefits from 243 ways to win. Land matching symbols on successive reels, starting from the leftmost reel, in order to win a payout. Three of a kind is the minimum for landing payouts, except when it comes to the Diamond, which pays even for two of a kind. Betting starts at $0.10 and the maximum wager is set at $40 per single spin.

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Casino Bloke Best tips for Who Wants to be a Millionaire Mystery Box Slot

  • 1The Mystery Box appears on reels 2, 3, and 4, revealing a randomly chosen symbol
  • 2Wilds and Scatters can also appear from the Mystery Box
  • 3Trigger up to 20 free spins at once, with a 2x multiplier
  • 4Each additional Scatter will get you an extra free spin, and allow you to climb the Multiplier Line
  • 5The win multiplier in the feature goes up to 50x
  • 6There is a Gamble feature on offer after every winning spin


The Mystery Box is a neat addition to the story because it will help gamers land wins more easily. It appears only on reels 2, 3, and 4, and, once landed, it will reveal a randomly chosen symbol. Even Wilds and Scatters can appear from the Mystery Box.

The Free Spins feature is triggered when three or more Scatters land on the reels. Players begin with 7, 12, or 20 free spins, depending on the number of Scatters landed, and a 2x win multiplier. Each time you land an extra Scatter on the reels during the feature, you will move one step up the multiplier ladder and get an extra freebie, except when you get to steps 4, 8, and 12, where you will get 3 extra free spins. Climb up the multiplier ladder and boost the win multiplier up to 50x.

Punters can also benefit from the Gamble feature after every win. Go for double or nothing up to five times.


In the original BTG title, the maximum possible payout was 50,000 times the bet. Now, the biggest win gamers can expect is set at 12,000 times the bet, and this you can win during the Free Spins feature, when you boost the win multiplier to 50x, which will not be easy. Who Wants to be a Millionaire Mystery Box’s RTP is 96.36%.

what we like

  • The Mystery Box is extremely helpful
  • Get additional freebies and a win multiplier up to 50x in the Free Spins feature
  • Wilds double wins when part of a winning combo

what we don’t like

  • Could use more authentic symbols from the TV show
  • Takes time to trigger freebies
  • Generic playing cards


We have said this when we reviewed the original video slot, but we will say it again – we do not like the fact that there is only one symbol from the TV show. There are plenty of similarities between the sequel and its predecessor in terms of visuals and the soundtrack. As for the special features, they have been upgraded. The Mystery Box will prove to be extremely helpful when you want to land a winning combo or when you want to trigger the Free Spins feature. Plenty of freebies are on the offer, especially when you land additional Scatters during the feature, which will also boost your win multiplier.

Who Wants to be a Millionaire Mystery Box Slot total score:

Total Score Overall

Game developed by:

Release year:2019

Available on:Desktop, Mobile

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