Thinking about giving Mermaid's Treasure: Book of Pearls a spin? We tested it thoroughly so you know what to expect. Developed by Nucleus Gaming, Mermaid's Treasure: Book of Pearls arrives with a medium low-variance maths model and a return-to-player rate of 95.38%. Visually it's themed around mermaid and fantasy, with the action running on 20 paylines across 5 reels. The maximum win sits at 2,000x, keeping expectations grounded but fair. Dating back to 2024, it remains a regular pick. So does it deliver? Let's get into it.
Written by James Holloway · Last updated: January 2026
Mermaid's Treasure: Book of Pearls comes to us from Nucleus Gaming, dressed up with a mermaid and fantasy theme and powered by 5 reels and 20 paylines. The result is medium low volatility paired with a return-to-player rate of 95.38%.
Dig into the bonuses and Mermaid's Treasure: Book of Pearls starts to stand out. Look out for scatter symbols that unlock free spins and extra bonus rounds. The medium low volatility makes it forgiving on the bankroll, ideal for relaxed, longer sessions. All told, it's a solid entry in the Nucleus Gaming catalogue.
At 95.38%, the RTP is slightly below the industry average of ~96%. While this is typical for many popular slots, players should be aware of the slightly lower theoretical return.
Medium-low volatility offers a good balance of regular wins with occasional larger payouts. Expect frequent hits with modest amounts, suitable for casual players who want low-risk entertainment.
About 1 in 3 spins results in a win. This is a moderate hit frequency that balances win frequency with payout size.
Mermaid's Treasure: Book of Pearls features scatter symbols that can trigger free spins rounds. Landing the required number of scatter symbols anywhere on the reels activates the free spins feature, giving you extra chances to win without additional bets. During free spins, special modifiers may apply to boost your winning potential.
3.0 / 5 — Good
Mermaid's Treasure: Book of Pearls by Nucleus Gaming is a solid offering that delivers good entertainment value. The 95.38% RTP combined with medium low volatility creates a well-balanced gaming experience.