Double Stacks (NetEnt) Slot Review

Double Stacks: Slot Overview 

Double Stacks is NetEnt’s vibrant tribute to classic fruit machine slots—revamped with modern mechanics, neon-soaked visuals, and a substantial payout ceiling. At first glance, it may seem like a modest game with just 10 paylines and a familiar 5×3 layout, but beneath the surface lies a high-volatility slot packed with explosive potential. 

With a maximum win of 10,000x your stake, 96.10% RTP, and a bonus round capable of delivering up to 30 free spins (with retriggers), Double Stacks stands out as a surprisingly powerful title. The core mechanics revolve around its titular Double Stacks feature, which allows stacked symbols to count as doubles, essentially letting players land up to 10 matching symbols per payline. 

The game’s retro 80s vibes, smooth animations, and pulse-pounding soundtrack make it an immersive experience that feels as much like an arcade game as a slot. With bet sizes ranging from €0.10 to €200, it appeals to both casual and serious slot players alike.

Design and Graphics 

Double Stacks exudes retro glamour. The reels glow in a palette of electric purples, pinks, and oranges, bathing the entire interface in neon light reminiscent of an 80s arcade or Las Vegas casino. Symbols include familiar fruit machine staples—cherries, lemons, plums, bells, bars, and sevens—rendered with a polished 3D-style shimmer.The interface is minimalistic but modern, with a classic layout that doesn’t clutter the screen. High-paying symbols like diamonds and sevens gleam with brilliance, while lower symbols retain a nostalgic charm. Reel spins are smooth, enhanced by neon flashes and sparkling transitions. 

Overall, the design is equal parts retro homage and visual polish. It’s unmistakably NetEnt in terms of animation quality and layout finesse, even though it draws inspiration from vintage fruit slots.

Gameplay Mechanics 

At the heart of Double Stacks is a simple yet potent mechanic: the ability for reels to display stacked symbols and activate a double symbol effect. Let’s break down the core gameplay features: 

Base Game 

5 reels, 3 rows, and 10 fixed paylines. 

Winning combinations are made by landing 3 or more matching symbols from left to right. 

All premium symbols (bells, bars, sevens, diamonds) can appear stacked. 

When a reel is filled with the same symbol, the Double Stacks feature activates—each symbol on that reel counts as two instead of one, allowing up to 10 matching symbols per payline. 

The highest-paying symbol, the diamond, pays 4.5x your stake for a 5-of-a-kind. 

This setup may sound simple, but it’s immensely satisfying. The chance of landing full-screen matches with doubled symbol counts gives every spin an added layer of excitement.

Sound and Music 

Double Stacks has one of the best soundtracks in NetEnt’s modern lineup. It’s a throwback to 80s synth music, with pulsing basslines, neon-fueled melodies, and subtle electronic flourishes. The sound design is more than just background noise—it’s an active part of the experience, adding rhythm and momentum to the gameplay. 

Symbol hits are met with zapping arcade effects and chimes that feel like they’ve been ripped straight from a retro pinball machine. When you land multiple doubles or enter the Free Spins mode, the tempo picks up and the audio swells with energetic cues that crank up the intensity. 

This isn’t just a slot with good music—it’s a slot where the music enhances the mechanics, making every win and near-miss feel that much more electric.

Bonus Features 

Double Stacks Feature 

This feature triggers when an entire reel stops with matching symbols. Every symbol on that reel then counts as two symbols for that spin. This is a game-changer, especially when combined with high-paying premium symbols. With this mechanic, even just a few paylines can lead to massive wins. 

Free Spins 

Triggered by landing 3, 4, or 5 scatter symbols anywhere on the reels, awarding:3 Scatters: 5 Free Spins 

4 Scatters: 15 Free Spins 

5 Scatters: 30 Free Spins 

During Free Spins: 

The 4 premium symbols and the Wild appear stacked. 

This increases the chance of full-screen combos and enhances the effectiveness of the Double Stacks mechanic. 

Additional scatters during Free Spins award 2, 5, 15, or 30 extra spins for 2, 3, 4, or 5 symbols respectively. 

Thanks to the combined effects of stacked wilds and Double Stacks, the Free Spins mode is where big wins can truly happen. With the right symbol alignment, it’s possible to achieve the game’s maximum payout of 10,000x your stake in a single spin.

Betting Options and Payouts 

Double Stacks is accessible to all bankrolls, with minimum bets starting at €0.10 and maximum bets reaching €200. This wide range makes the game friendly to low-stakes players while still appealing to high-rollers looking for high-volatility action. 

Paytable Overview: 

Diamond (top symbol): 4.5x for 5 on a line 

Sevens: 3x for 5 

Bar: 2x for 5 

Bell: 1.5x for 5 

Fruit symbols (Plum, Lemon, Cherry, Watermelon): 0.6x to 1x 

Wild: Substitutes for all symbols except scatter; appears stacked only in Free Spins 

Scatter: Triggers Free Spins and retriggers within bonus 

Additional Stats: 

RTP: 96.10% 

Volatility: High 

Hit Frequency: 16.2% 

Free Spins Frequency: 0.36% 

Max Win: 10,000x stake per spin 

While base game payouts are modest, the inclusion of the Double Stacks feature adds high-value potential even outside the bonus. But make no mistake—this is a high volatility slot, and big wins come in short bursts, often tied to the bonus rounds.

Conclusion 

Double Stacks is NetEnt’s successful fusion of classic slot aesthetics with modern, high-payout gameplay. At first glance, it might not seem like a game with huge potential—but once you experience the synergy between Double Stacks, stacked wilds, and the Free Spins, it becomes clear that this is a sleeper hit. 

The visuals are crisp, the 80s-inspired soundtrack is among the best in NetEnt’s portfolio, and the gameplay loop is as addictive as it is rewarding. With a potential 10,000x win per spin, it offers a genuine thrill for players chasing big rewards. And the fact that premium symbols can double across reels means there’s a constant feeling of suspense and satisfaction on every spin. 

If there’s a downside, it lies in the game’s low base hit frequency (16.2%) and the sometimes elusive bonus round. But these traits are typical for high-volatility slots, and they’re a trade-off for the chance to land that elusive mega win.