Book of Abyss by Just Slots: headline RTP 94.31%, max win x15 000.
An RTP of 94.31% means a house edge of 5.69% — the expected cost is 5.69 units per 100 staked over the long run, whatever a single session does.
The advertised ceiling is x15 000. Max win figures describe the tail of the distribution, not a realistic target: on most games with a ceiling this high the probability per spin is below one in a million.
Against our catalogue the number is below the median of 96.13%, higher than 11% of the games whose RTP we verified. That comparison matters more than the raw figure, because "96%" only sounds generous next to nothing.
Released 2025-11-13. Release date matters for RTP: newer titles are more likely to ship with several configurable builds, which is what lets two casinos price the same game differently.
Book of Abyss is one of 14 Just Slots titles in our catalogue, a studio averaging 95.80% RTP across the games we could verify.
See the full Just Slots game list and RTP breakdown.
This title is tagged Book Of, Halloween. A theme is art direction, not maths — two games sharing every symbol can be priced differently.
Book of Abyss has a published RTP of 94.31%, a house edge of 5.69%. We have not yet found a casino serving it at a different RTP build.
Yes. Book of Abyss has a free demo with the same mathematics as the real-money version — the only thing that changes is that the balance is not yours. A demo cannot tell you the RTP build a particular casino serves.
Book of Abyss is a Just Slots game, so the outcome is produced by the studio's certified RNG rather than by the casino, and it is not provably fair in the cryptographic sense — you cannot recompute a spin from a seed. What the casino does control is which RTP build it serves. That is the real variable, and it is measurable.