Millionaire Mystery Box Slot

Discover the excitement of the Millionaire Mystery Box slot game inspired by the popular TV show. With mystery boxes revealing special symbols, double-paying wilds, and a thrilling free spins round, you can win big across 243 ways to win. With an RTP of 96.642%, enjoy the gamble feature for extra wins. Land scatters to climb the multiplier ladder for up to 50x your prize. Explore more Big Time Gaming slots, including the Megaways version. Sing the praises of this thrilling game and play now on mobile or tablet at recommended online casinos.

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Review of the Millionaire Mystery Box Slot

The Millionaire Mystery Box slot game from Big Time Gaming is inspired by the popular TV show Who Wants To Be A Millionaire. You won’t need to phone a friend to share how amazing it is though. This slot features mystery boxes that reveal special symbols, wilds that can double your winnings, and scatter symbols that trigger an impressive free spins round with generous multipliers.

While you can’t ask the audience for help in this game, be sure to explore our complete review of the Millionaire Mystery Box slot for all the essential information.

Experience a Slot Based on an Iconic Game Show

Who Wants To Be A Millionaire is a globally renowned game show, and Big Time Gaming deserves credit for adding a unique twist to their Millionaire Mystery Box online slot. In addition to classic poker cards and gemstones like emeralds, rubies, sapphires, and amethysts, this slot offers exciting features such as double-paying wilds, mystery boxes, and scatters that can activate a free spins feature where you can climb a multiplier ladder.

Enjoy 243 Ways to Win

The Millionaire Mystery Box slot game does not use traditional paylines. Instead, players can enjoy an impressive 243 ways to win on its 5 reels. With a minimum bet of just 0.10 coins per spin, and a range of 25 different bet amounts up to a maximum of 40.00 coins, there are plenty of options for all players to enjoy. The game has a return-to-player (RTP) percentage of 96.642%.

Climb the Leaderboard

In the Millionaire Mystery Box online slot, you can win prizes by matching three to five poker or gem symbols, with just two amethysts needed for a win. Wilds can help complete winning combinations on reels two, three, and four, doubling the payouts. Mystery boxes on these reels can reveal special symbols to boost your winnings, with a gamble feature available to potentially increase your prizes up to five times.

The highlight symbols to land are the Who Wants To Be A Millionaire Mystery Box scatters. Landing three, four, or five scatters triggers 7, 12, or 20 free spins respectively. During the free spins, players have the chance to win numerous prizes, with additional scatters aiding in climbing the multiplier ladder towards bigger wins.

Each scatter obtained moves you up the ladder, awarding extra spins and increasing multipliers. Reaching the 12th rung results in all prizes being multiplied by 50x – a fantastic incentive to spin the Millionaire Mystery Box slot game.

Explore More Big Time Gaming Slots

The Millionaire Mystery Box slot is not the only game based on Who Wants To Be A Millionaire from Big Time Gaming. Players can also enjoy the Who Wants To Be A Millionaire Megaways slot game, offering an impressive 117,649 ways to win, along with unique features like an extra reel, cascading symbols, wilds, free spins, and multipliers.

If you’re looking for other high-paying slots, Big Time Gaming offers titles like Danger High Voltage, Faeries Fortune, and Starquest. For a unique gaming experience, consider spinning the reels of Opal Fruits, a game featuring a Triple Reaction Feature.

Praise for This Slot Game

There’s a song titled Who Wants To Be A Millionaire, but you’ll likely be singing the praises of the Millionaire Mystery Box slot instead. With double-paying wilds, mystery box features, and a thrilling free spins round with multipliers of up to 50x, this slot offers a lot to enjoy.

Your decisions involve whether to play on mobile or tablet and selecting one of our recommended online casinos. Play Millionaire Mystery Box for free or real money now, or explore other exciting titles from Big Time Gaming below.

Jack Barens, ReallyBestSlots writer
Jack Barens iGaming Writer
Last Updated: October 5, 2025
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