Book of Monsters
Pragmatic Play's Book of Monsters is a monster-themed cluster-pays slot where symbol blocks of varying sizes, from 3x3 up to 7x7, can appear on any base game spin. Landing 4 to 7 bonus symbols triggers 5 to 8 free spins, during which a randomly chosen Fat symbol can expand up to 7x7, granting extra spins as it grows. Before the free spins begin, players may gamble to raise the spin count or upgrade the Fat symbol.
RTP published by the studio / Book of Monsters
96.5%
Scale starts at 95% · other versions not published
Figures: Pragmatic Play game page, Pragmatic Play demo game, checked October 6, 2026; each value is linked to its page in the game facts table. Artwork © Pragmatic Play; image file from the Slots-Info slot database, not supplied by the studio.
5,000×
Max win, × stake
1
RTP version published · others not published
Yes
Bonus buy
Game facts
| Metric | Value |
|---|---|
| Studio | Pragmatic Play1 |
| RTP versions | 96.5%1 |
| Other RTP versions | Not published by the studio |
| Volatility | Not published |
| Max win | 5,000× stake2 |
| Bet range | Not published by the studio |
| Layout | 7x7 · Cluster pays1 |
| Features | Supersized Symbols, Free Spins, Fat Symbol growth, Gamble feature, Bonus buy, Ante bet1 |
| Bonus buy | Yes2 |
| Release date | March 27, 20253 |
Numbers link each value to the page it comes from. “Not published” means the studio does not state it; we add it when it does and never estimate a spec. Figures from casino sites are not used.
RTP versions
Pragmatic Play publishes one RTP setting for Book of Monsters: 96.5%. Other RTP versions are not published by the studio. Check the game’s help or paytable screen at your casino to see which version it runs.
| RTP version | House edge | Return per $100, long run | vs highest |
|---|---|---|---|
| 96.5% (highest) | 3.50% | $96.50 | — |
House edge = 100% minus RTP. RTP is a long-run average across all players, not a prediction for a session.
Features
- Supersized Symbols
- Free Spins
- Fat Symbol growth
- Gamble feature
- Bonus buy
- Ante bet
Where it’s available
Not confirmed. Availability in regulated North American markets is not confirmed yet.
Regulated markets only; availability varies by casino.
