Return to player
96.5%
Min bet size
0.20
Game type
Video Slots
Variance
High
Reels
7
Progressive Jackpot
No
Popularity
Max bet size
480
Game provider
Pragmatic Play
Bonus Features
Yes
Paylines
Cluster Pays
Theme
Monsters
Book of Monsters online slot game
Yet another wicked adaptation of the Monsters, Inc. theme has emerged with Pragmatic Play's Book of Monsters. This cluster-pays slot is filled with wide-eyed, toothy-grinned creatures that don’t quite resemble the beasts they are made out to be. Of course, the cave they inhabit is undeniably spooky, with its glowing specters and eerie, fog-laden surroundings. Amidst the mystery and thrill, prepare to embark on a wild adventure where quirky critters, hidden secrets, and big wins await around every corner!
The Book of Monsters Slot at a Glance: All the Important Facts to Know
- Book of Monsters has an RTP of 96.50%.
- The slot uses a Cluster Pays system.
- Bonus features include Free Spins, Ante Bet, and Bonus Buy.
- Extra spins are awarded each time the special Fat symbols grow in size.
Graphics and Sound of the Book of Monsters Slot
The graphics of Book of Monsters showcase friendly-looking creatures floating harmlessly in their own little world, while more sinister beings lurk in the corners with glowing eyes and menacing grins. The rugged, rocky backdrop resembles a forgotten cavern, pulsing with soft blue energy.
That is, until Free Spins activate, turning the cave into a glowing orange abyss. On the right, an enchanted tome hovers above a stone pedestal, triggering transformations that may startle the burrow’s inhabitants but work in the player’s favor.
Every shift in the game is heightened by a blend of suspenseful hums, squeaky tones, and bouncy vocalizations that intensify the rush of unlocking the cave’s best-kept secrets. Overall, Book of Monsters offers a chilling yet entertaining slot experience that keeps players on their toes.
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How to Play the Book of Monsters Slot
Book of Monsters is a 7x7 slot game that transports players to a realm inhabited by mischievous little creatures, burdened by the inability to control their own growth. Wins are formed when clusters of at least five matching symbols connect vertically and/or horizontally on adjacent reels.
On the main game board, players will encounter two sets of symbols. Low-paying icons consist of classic royal playing card letters, J, Q, K, and A, while high-paying symbols include three distinct monsters in purple, green, and red.
Although there are no Wilds, so-called ‘Fat symbols’ of sizes 3x3, 4x4, 5x5, 6x6, or 7x7 may hit randomly during the base game, significantly boosting winning potential. Key bonus features include Free Spins, the Ante Bet, and a Bonus Buy option, doubling the excitement in this monstrous adventure.
Using the Book of Monsters demo version
Set off on an unforgettable journey through the narrow caves and hidden crevices of Book of Monsters' underground dwelling with the free-play version on PlayCasino. The demo mode offers the perfect opportunity to explore the gameplay mechanics, special symbols, and bonus features without any financial risk. Take your time to navigate each aspect of the game and determine if it aligns with your preferences before wagering real money.
Bonus Features in the Book of Monsters Slot
Book of Monsters may not have a wide range of bonus features, but its free spins can still lead to big wins. Let’s take a closer look at how they work:
Free Spins Feature: An orange alien serves as a Bonus Scatter in the Book of Monsters slot. Landing 4, 5, 6, or 7 of these bonus symbols triggers the Free Spins feature, awarding 5, 6, 7, or 8 free spins, respectively.
Before the round starts, a random pay symbol is chosen as the Fat symbol. Players can opt to gamble the Fat symbol for a more valuable one or gamble their spins for additional free spins. Alternatively, they can collect the current Fat symbol and free spins to begin the feature.
If players choose to gamble for free spins or a better Fat symbol and the monster book reveals 'The End', the bonus round ends immediately. Otherwise, a successful gamble can earn up to 8 extra free spins and upgrade the Fat symbol to the highest value symbol possible.
Additionally, the free spins round features a progressive mechanic involving the Fat symbol. Initially appearing as a 1x1 icon on the grid, it moves to a new position with each spin. Any instances of the Fat symbol that appear during the round, excluding those overlapped by the Fat symbol itself, are collected in a meter. Once a specific threshold is reached, the Fat symbol increases in size. There are six possible sizes:
- Collect 30 to upgrade the Fat symbol size to 2x2.
- Collect an additional 27 to upgrade it to 3x3.
- Collect 24 more to upgrade it to 4x4.
- Collect 20 more to upgrade it to 5x5.
- Collect 16 more to upgrade it to 6x6.
- Collect 12 more to upgrade it to 7x7.
Each time the Fat symbol grows in size, it randomly awards an extra 1, 2, or 3 free spins.
Ante Bet: Before starting the game, players can choose a bet multiplier. The selected stake affects gameplay in the following ways:
- 40x bet multiplier – The chance of triggering the Free Spins feature is seven times higher. Landing 3, 4, 5, 6, or 7 bonus symbols awards 4, 5, 6, 7, or 8 free spins, respectively.
- 20x bet multiplier – The game operates normally with no additional advantages.
Bonus Buy: The Free Spins round can be instantly triggered from the base game by purchasing it for 100x the current total bet. On random, a triggering spin may land 4, 5, 6, or 7 Bonus symbols.
Winning Strategies for the Book of Monsters Slot
When playing Book of Monsters, you can utilize the following tips and tricks to maximize your chances and manage your balance effectively:
- Choose the right bet multiplier: If you want a greater probability of triggering free spins, the 40x bet multiplier increases your odds by 7x. However, if you prefer a lower-risk approach, you can stick to the standard gameplay with balanced volatility.
- Consider buying the bonus feature: If you have a larger bankroll and want to skip the base game, buying the Free Spins feature for 100x your total bet can be a viable option. You may also win additional free spins during the feature, further boosting your potential returns.
All the Technical Details
Pragmatic Play's Book of Monsters is a cluster-pays slot with a 96.5% RTP and high volatility. Bets range from 0.20 to 240 per spin, offering a massive winning potential of up to 5,000x the stake. The slot also features unique ‘Fat Symbols,’ which progressively grow during free spins, adding an extra layer of excitement to the gameplay and greatly increasing the chances of landing big rewards.
Best Alternatives to the Book of Monsters Slot
If you're interested in more monster-themed slot games, play these notable titles that offer thrilling experiences:
- Aliens: Aliens is a 96.4% RTP slot by NetEnt, based on the blockbuster movie we've all come to adore—and fear just as much! Check out this five-reel, 15-payline take on an epic intergalactic adventure, filled with bloodthirsty aliens, rewarding bonus rounds, and superb collectable multipliers.
- Immortal Romance: Immortal Romance is a 96.96% RTP slot with 243 ways to win. It features an engaging storyline, stunning graphics, and four unique free spins rounds that can lead to substantial wins. Plus, you can enjoy seamless gameplay on both mobile and desktop without any disruptions.
Our Verdict
Book of Monsters is a fairly straightforward slot where a book randomly selects a special symbol and awards free spins. However, there's a risk of losing the bonus round entirely, which may make the experience feel somewhat restrictive. The base game might also come across as a bit dull on its own, and the high volatility could deter casual players seeking a more moderate challenge. That said, the growing Fat symbol adds a touch of amusement and offers the potential for substantial wins, making this slot worth a try at least once.
James is a casino games expert on the Playcasino.com editorial team. With many years of professional experience at a leading casino game development company and a passion for playing casino games, James has become a true expert in slots, blackjack, roulette, baccarat, and other games.
James uses this expertise to provide reliable, insider advice through his reviews and guides, breaking down the game rules and offering tips to help you win more often. Rely on James's extensive experience for expert advice on your casino play.
