Searching for an honest Book of Sirens review before you commit real money? You're in the right place. Developed by Spinomenal, Book of Sirens arrives with high variance and a published RTP of 95.95%. Originally released in 2022, it has aged well. Visually it's wrapped in a book of theme, with the action running on 20 paylines across 5 reels. The maximum win sits at 500,000x, so there's serious upside on the table. But is it actually worth playing? Read on.
Written by Alex Crawford · Last updated: February 2026
Book of Sirens is a slot game from Spinomenal. Presentation-wise it's themed around book of, and it leans toward a high volatility profile at an RTP of 95.95%. Under the hood you'll find 5 reels and 20 paylines.
The mechanics are what make Book of Sirens interesting. Look out for scatter symbols that unlock free spins and extra bonus rounds. With high variance, this one is aimed at players who can ride out the swings for the top wins. All told, it's a solid entry in the Spinomenal catalogue.
At 95.95%, 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.
High volatility means longer gaps between wins, but when wins do land, they can be significantly larger. A bigger bankroll and patience are recommended for this type of slot.
About 1 in 3 spins results in a win. This is a moderate hit frequency that balances win frequency with payout size.
Book of Sirens 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
Book of Sirens by Spinomenal is a solid offering that delivers good entertainment value. The 95.95% RTP combined with high volatility creates a well-balanced gaming experience.