Mystery Stacks

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Rules and Gameplay

The Mystery Stacks slot series by Silverback Gaming features a standard 5×3 layout with gameplay that combines traditional slot mechanics with modern twists. Players set their stakes between $0.10 and $1,000, accommodating both low rollers and high-stakes players. Winning paylines can start from anywhere within the grid, ensuring dynamic and engaging gameplay. The inclusion of demo modes across versions allows players to familiarize themselves with the game’s mechanics and features without risking real money, making these slots accessible to both newcomers and seasoned enthusiasts.

Bonus Features

The Mystery Stacks slots are equipped with unique and exciting bonus features designed to enhance the gaming experience. Key features include:

  • Mystery Coins: These symbols transform to reveal a matching symbol, increasing the chances of hitting a winning combination.
  • Mega Coin: Acts similarly to Mystery Coins but guarantees a win by filling the reels with one symbol.
  • Free Spins: Triggered by scatter symbols, offering players additional spins without deduction from their balance.
  • Walking and Multiplying Wilds: Available in the Deluxe version during free spins, these wilds move across the reels and can multiply, potentially leading to larger wins.
  • Bonus Wheel: Present in Mystery Stacks Deluxe, it offers a chance for a max win of 1,000x or additional free spins.


The symbols in Mystery Stacks slot games pay homage to classic slot imagery while incorporating modern design. Key symbols include:

  • Fruit symbols (Cherries, Lemons, Oranges, Plums, Watermelons): Represent lower-value symbols.
  • Bell: The highest-paying symbol, offering significant payouts for matching combinations.
  • BAR symbols (Single, Double, Triple): Mid-value symbols with varying payouts.
  • Special Symbols (Mystery Coin, Mega Coin, Wilds, Scatters): Trigger bonus features and enhance winning potential.


The Mystery Stacks slots offer lucrative payouts, with the potential for massive wins. Here’s an overview of payout values based on a maximum bet of $1,000:

Symbol 3 Symbols 4 Symbols 5 Symbols
Bell $10,000 $30,000 $50,000
Triple BAR $6,000 $10,000 $30,000
Double BAR / Single BAR $4,000 $10,000 $30,000
Fruits Varies Varies Up to $20,000

For detailed payouts at different bet values, players should refer to the game’s paytable.


Mystery Stacks slots feature 10 paylines, providing multiple opportunities for winning combinations. Paylines can be activated from anywhere within the grid, allowing for flexibility in winning patterns. This design ensures that players have a good chance of landing winning combinations, enhancing the excitement and appeal of the game.

Pros & Cons

Pros Cons
Engaging and vibrant retro theme Lack of progressive jackpot
Wide betting range suitable for all players Limited innovation in bonus features
Multiple special symbols and bonus features for increased winning chances Potential for repetitiveness over extended play sessions

Minimum and Maximum Bet

The Mystery Stacks series offers a flexible betting range designed to accommodate every type of player. Bets start as low as $0.10, making it accessible for players on a budget or those who prefer to play it safe. On the other end of the spectrum, the game accepts bets up to $1,000 per spin, catering to high rollers looking for the thrill of placing large wagers. This wide betting range ensures that the game can be enjoyed by everyone, regardless of their bankroll size.

Game Jackpot

The Mystery Stacks slots do not feature a progressive jackpot, but players can still win big with a maximum payout. The game’s RTP is set at a competitive 95.00% to 95.52%, indicating a fair return to player over time. With medium to high volatility, players can expect a mix of frequent small wins and the occasional large payout. This balance makes the game appealing to both casual players and those seeking the adrenaline rush of significant wins.

About Provider

Silverback Gaming is the creative force behind the Mystery Stacks series. As a provider known for its innovative approach to slot design, Silverback Gaming combines engaging themes with exciting gameplay mechanics. The company emphasizes creativity, simplicity, and elegance, traits that are evident in the Mystery Stacks series. Through its partnership with Relax Gaming’s Silver Bullet platform, Silverback Gaming has expanded its reach, delivering high-quality gaming experiences to a wider audience.

How To Play

  1. Start by loading the Mystery Stacks game on your chosen platform.
  2. Adjust your bet size using the game’s controls. You can select a minimum bet of $0.10 or increase it up to $1,000, depending on your preference and bankroll.
  3. Review the paytable to understand the payouts and special features like Mystery Coins and Mega Coins.
  4. Press the spin button to start the game. Winning combinations will be highlighted, and payouts will be added to your balance.
  5. Keep an eye out for special symbols that can trigger bonus features for additional chances to win.
  6. Utilize the auto-play feature for a predetermined number of spins if available, allowing you to sit back and watch the action unfold.
  7. Manage your bankroll responsibly, adjusting your bet size as needed to ensure a enjoyable gaming experience.


The Mystery Stacks series by Silverback Gaming stands out with its vibrant retro theme, engaging gameplay, and innovative features like Mystery and Mega Coins. Despite the lack of a progressive jackpot, the game offers significant winning potential through its special symbols and bonus rounds. The wide betting range makes it accessible to a broad spectrum of players, from beginners to high rollers. Silverback Gaming’s dedication to combining simplicity with excitement is evident, making the Mystery Stacks series a must-try for slot enthusiasts looking for a modern twist on classic slot gaming.