Book of Monsters Slot Review

The Book of Monsters Slot Game

Book of Monsters from Pragmatic Play looks like a horror title on paper, yet the reality is much lighter. The action takes place in a glowing underground cave, with cheeky, cartoon-style monsters huddled around a 7x7 grid framed by stone. To the side, a steaming magical book hovers above a pedestal, ready to spring into life. Wins use a cluster-paying system, with at least five matching symbols touching horizontally or vertically.

The base game in Book of Monsters is quite stripped back, which I felt straight away. There are no cascades and no wild symbols, so most spins are about lining up decent clusters. The main twist comes from occasional Fat Symbols, where the book spits out 3x3 to 7x7 blocks of one paying symbol. Stakes range roughly from €0.20 up to €240 a spin, so there is plenty of room to size bets sensibly.

Symbols and Payouts in Book of Monsters

The paytable in Book of Monsters keeps things tidy with seven regular symbols. Low pays are card ranks carved into rocks, showing Jack of Diamonds, Queen of Clubs, King of Hearts, and Ace of Spades. Using cluster pays, any connected group of five or more of the same symbol will pay. For 5 to 49 of a kind, the card symbols pay from 0.2x up to 200x the stake, depending on rank and cluster size.

Premiums are three monster icons, coloured purple, green, and red. These step up the prizes, starting at 0.5x to 2x the bet for 5-symbol clusters and climbing right up to 250x, 500x, and 5,000x the stake for a full 49-symbol cluster of each monster, with the red one sitting top. The only special symbol is the Bonus icon with a staring orange eye, paying 2x to 100x and triggering free spins when enough land together.

Symbols and Paytable

Symbol	Quantity	Payout
	49+	x5000
	40+	x500
	7	x6
	6	x4
	5	x2
	49+	x500
	40+	x250
	7	x3
	6	x2
	5	x1
	49+	x250
	40+	x125
	7	x1.5
	6	x1
	5	x0.5
	49+	x200
	40+	x100
	7	x1.25
	6	x0.75
	5	x0.4
	49+	x150
	40+	x75
	7	x1
	6	x0.6
	5	x0.3
	49+	x125
	40+	x62.5
	7	x0.75
	6	x0.5
	5	x0.25
	49+	x100
	40+	x50
	7	x0.6
	6	x0.4
	5	x0.2
	Scatter

Book of Monsters Slot Bonus Features

Book of Monsters revolves around its bonus features rather than flashy base game modifiers. Landing 4, 5, 6, or 7 Bonus symbols in one spin awards 5, 6, 7, or 8 free spins, plus a payout. With the ante bet active, the requirement drops to 3 to 7 Bonus symbols for 4 to 8 spins, and the chance of triggering the feature is said to jump seven-fold compared with standard play.

Before the free spins start, the book picks a random paying symbol to act as the Fat Symbol for the round. At this point I can gamble the starting setup in two ways. One gamble can increase the number of free spins, while the other can upgrade the Fat Symbol to the next symbol in the paytable. If the book flips to The End after a gamble, the whole bonus vanishes and I am dumped back into the base game.

Inside the free spins, the chosen Fat Symbol begins as a 1x1 tile that wanders to a new grid position on every spin. Any matching symbols landing that are not covered by the roaming tile fill a collection meter. Hitting set thresholds grows the Fat Symbol from 1x1 up through 2x2, 3x3, 4x4, 5x5, 6x6 and finally 7x7, while also awarding 1 to 3 extra spins each time. There is also a bonus buy option at 100x bet, letting me jump straight into this feature.

Bonus Buy Feature

Free Spins Round FREE SPINS round can be purchased for 100x of the total bet. When buying a round, 4, 5, 6 or 7 BONUS symbols can appear randomly.
Feature Cost:	x100 Bet
RTP:	96.50%
Volatility:	-

How to Win at Book of Monsters Slot

Winning in Book of Monsters comes down to managing a cluster-paying 7x7 grid and making the most of the Fat Symbol mechanics. I am always chasing blocks of at least five identical symbols connected side by side or vertically; multiple clusters pay together on one spin. The theoretical cap is 5,000x the stake, which matches a full grid of the top red monster. I usually use smaller stakes, around €0.20 to €1, when experimenting with the ante bet or bonus buy.

Book of Monsters Slot RTP & Volatility

On the numbers side, Book of Monsters runs with high volatility and a default RTP of 96.5%, though some sites may use slightly lower configurations. Official figures put the hit frequency at about 23.2%, so regular small clusters show up, but the game saves its real punch for the bonus. The maximum win sits at 5,000x the bet, with studio data suggesting that outcome arrives roughly once in 547,945 spins, and the bonus triggers on average every 291 spins.

The Final Verdict on Book of Monsters

When I first saw the title Book of Monsters, I was expecting a standard five-reel Book-style slot with straightforward expanding symbols. Instead, Pragmatic Play has gone with a 7x7 cluster-paying layout, no cascades, and a single roaming Fat Symbol carrying the bonus game. The base game can feel flat between features, especially with no wilds or tumbles to spice up streaks, but random Fat Symbols do occasionally shake things up with outsized clusters.

For me, the real entertainment lies in the free spins. The pre-bonus gamble screens introduce a proper sweat, as you weigh up more spins or a better Fat Symbol against the risk of seeing The End. Once inside, watching the Fat Symbol grow across the grid, picking up extra spins, gives a nice sense of progression. The 5,000x cap is fairly standard for a cluster slot, yet the mix of quirky visuals and progressive mechanic keeps me coming back for another session.

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