When the reels first land
Each spin lands on a 7x7 grid, and a win needs at least 5 connected symbols, linked horizontally or vertically. A FAT symbol, a block from 3x3 up to 7x7, can appear at random on each spin.
Before any spinCluster pays
Pragmatic Play · 2025
Book of Monsters
Book of Monsters is a high volatility video slot from Pragmatic Play, played on a 7x7 cluster grid with horror monsters and free spins.
- RTP 96.50%
- Volatility High
On this page
Book of Monsters
Book of Monsters figures and what each one means
This table settles what each figure means for your stake before you spin.
| What it measures | As shown |
|---|---|
| Provider | Pragmatic Play |
| Return to player | 96.50% |
| Volatility | High |
| Maximum win multiple | x5,000 |
| Maximum win in money | A$2,400,000 |
| Release date | 27/03/2025 |
Learn the Book of Monsters before you bet
Symbols land on a 7x7 grid, and a win forms when at least five matching symbols connect horizontally or vertically. Clusters pay, so no fixed paylines decide the result. The theme is horror and monsters, with three monster symbols in red, green and purple plus the playing-card symbols A, K, Q and J. A FAT symbol, a block of three by three up to seven by seven cells, can appear at random.
Four or more BONUS symbols on the reels start the Free Spins, which award five to eight spins. The chosen FAT symbol begins at one cell and grows to seven by seven as its instances are collected, and each size-up adds one to three spins. A Gamble screen before each round can raise the FAT tier or spin count, or collect and start.
Quick Walkthrough
What one round of this slot gives you
Casino Rocket walks you through a single round in plain language, without the guesswork.
Setting Your Stake
You set your stake anywhere from A$0.20 to A$480 before the grid spins. Our examples use A$0.40 and A$0.50, but they are just examples, not the limits of the game.
Watching The Grid Connect
Wins come from clusters, not lines: five or more matching symbols joined horizontally or vertically on the 7x7 grid pay out. More joined symbols mean a bigger cluster, and the total lands in your balance straight away.
The Bigger Block Advantage
A fat symbol can drop in as a block from 3x3 up to 7x7, shifting the layout each spin. Under the ante bet the free spins trigger drops to three bonus symbols, seven times more often.
From Four Symbols To A Growing Block
Four or more bonus symbols start the free spins, five to eight of them, and a gamble screen before the round. The chosen fat symbol starts small and grows to 7x7 as copies land, each size-up adding one to three spins.
Fix Your Limit First
Decide your stopping point before you tap spin, and treat the gamble screen as part of your stake, not as extra. If hitting that point feels close, stop there and come back another time.
Know what pays
Book of Monsters payout table by symbol
Clusters on the reels pay the amounts below in money at the A$0.40 example bet, and more matching symbols pay more.
| Which one | 28+ | 31+ | 40+ | 49+ |
|---|---|---|---|---|
 BONUSScatter | – | – | – | – |
 Red Monster | A$20 | A$40 | A$100 | A$1,000 |
 Green Monster | A$10 | A$20 | A$50 | A$100 |
 Purple Monster | A$5 | A$10 | A$25 | A$50 |
 Ace | A$4 | A$8 | A$20 | A$40 |
 King | A$3 | A$6 | A$15 | A$30 |
 Queen | A$2.50 | A$5 | A$12.50 | A$25 |
 Jack | A$2 | A$4 | A$10 | A$20 |
Bonus guide
Triggers, upgrades and feature menu
Read this before you choose a bet size, a mode or a feature.
Fewer BONUS symbols to start
3 BONUS symbols on the reels start the free spins when the Ante Bet is on, where 4+ are needed without it. That gives a 7x higher trigger frequency. Buy Free Spins is switched off while the Ante Bet is active.
Standard betEasier trigger
Growing the FAT symbol to 7x7
4+ BONUS symbols on the reels start the round, or 3+ with the Ante Bet on. Buying it costs 100x your bet. You get 5-8 spins, and a selected FAT symbol starts at 1x1 and grows to 7x7 as its instances are collected. Each size-up adds 1-3 spins.
Base game spins5-8 free spins
What You Will See
Before the bonus, during the round
After reading this, you will know what each screen shows before you spin.
Free spins begun, chosen fat symbol rising 
Gamble screen offering tiers or spins 
Fat symbol grown large across the grid
What the buy and ante bet take
On the reels, the buy skips the wait for four BONUS symbols and costs 100 times the bet, priced in money below.
| Optional add-on | Money cost | RTP |
|---|---|---|
| Buy Free Spins | x100 · A$50 | – |
What return to player means for each stake
Clusters of linked symbols decide each payout, and return to player shows how much of every A$100 staked comes back over time. The version this lobby runs appears in the game rules.
| Payback tier | RTP | Provider default? |
|---|---|---|
| Version 1 | 96.50% | Yes |
Can anyone predict the next bonus round?
Clusters of matching symbols form and vanish on the 7x7 grid with every spin, and the Free Spins round appears at random. How often that round comes is not known in advance. The result of one session is random whatever the RTP, so a published RTP does not promise a winning session.
Connected symbols on the 7x7 grid pay once five or more of them touch horizontally or vertically, so the reels reward groups instead of paylines. Which RTP version Casino Rocket runs is shown only in the game rules, so read that screen before the first spin.
Blocks of FAT symbols may land at random on the grid, yet the maximum win of Book of Monsters is a ceiling reached very rarely. Its multiple is shown in the figures table, and the money value depends on the bet you choose, so treat the top figure as a limit, not a target.
Practice Mode
Test the game before the first wager, then decide
Casino Rocket lets you watch the reels move before any money leaves your account.
The demo needs no money and pays nothing, so you can learn the reels first. Real play needs a Casino Rocket account and you must be 18 or older.
Start playingBudget, limits and pauses
Play is for adults aged 18+ only. For support, call the National Gambling Helpline on 1800 858 858, or register with BetStop, the national self-exclusion register.
Know your loss amount first
Decide how much you can afford to lose before you open Book of Monsters, and leave that amount aside for the session.
Set your stop point first
Choose your stop point before the first spin, and keep to it even after a large win or a long run of losses.
When your budget changes
Set the deposit and loss limits in your account before a session, and lower them if your budget changes.
When does a pause help?
If Book of Monsters stops being fun, pause the session and come back another day, or self-exclude when the break does not help.
Pick a better match
Compare Fortune of Olympus before you commit
Many players fear every slot plays alike, so this page compares the lobby.
Before the first round
What would you ask about Book of Monsters?
Most players worry about money and odds before a spin, so these answers keep the figures plain.
Is Book of Monsters a high volatility slot?
This slot has high volatility. Wins tend to be less frequent, but they can be much larger than the bet, with a top win of 5,000 times the bet. How often a big win lands cannot be known before you play.
How do I trigger the free spins in Book of Monsters?
Four or more BONUS symbols on the reels start the free spins, and they award 5 to 8 spins. With the Ante Bet turned on, three BONUS symbols are enough, which raises the trigger frequency seven times.
What is the minimum and maximum bet on Book of Monsters?
Bets run from A$0.20 up to A$480, the highest bet allowed in this market. The Ante Bet raises the cost of each spin to 2 times the bet, and it cannot be combined with buying free spins.
What is the RTP of Book of Monsters and are there different versions?
One RTP version applies, at 96.50 percent. RTP is the average return over a very large number of spins, not a promise for any single session. Short sessions can end with much more or much less than that average.
Can I buy the free spins in Book of Monsters and what does it cost?
Buy Free Spins is available in Book of Monsters, and it starts the free spins round directly for 100 times the bet. The price follows the bet, so a higher bet means a higher price. The buy is disabled while the Ante Bet is active.
Nathan Greer
Senior editor, former payments compliance analyst
I check each payment method against its deposit and withdrawal limits, and I rewrite the bonus terms until the wagering requirements read plainly for a player.