Book of Monsters: Slot Overview
It might sound like a bit of light reading at Hogwarts School of Witchcraft and Wizardry, but software provider Pragmatic Play's Book of Monsters is actually a cluster-paying grid slot. It is not, strictly speaking, a 'Book of' slot where special symbols expand to cover their reels, but books do flip open to reveal free spins and randomly chosen symbols. These randomly chosen symbols do expand in the bonus round, but they act more in the manner of a Fat Rabbit than a Book of Dead.
This might be a game about monsters, but the monsters on the reels and book don't look like the kind who hide under beds to scare kids or get up to any sort of bad deeds, really. Rather, their wide eye, toothy grins give them a Reactoonz vibe, more interested in participating in harmless acts of mischief than anything actually nasty. The monsters inhabit a cave, which, okay, is populated by scary, glowing-eyed spectres, bathed in a blue light that shifts to orangey when free spins trigger. Hopefully, you see a lot of orange because Book of Monsters' thrills probably have a greater likelihood of occurring in the bonus round.
Played on a 7x7 grid, Book of Monsters operates a cluster pays win system, creating winning combinations when at least 5 matching symbols are adjacent to each other vertically and/or horizontally. The base game is pretty much feature-free, so players can buy into the bonus round or use the ante bet to make it 7 times more likely to trigger free spins. Base bets of 20 c to $/€240 may be selected, and when the ante bet is active, the stake is doubled. Highly volatile, the top RTP for all options is 96.5%.
Book of Monsters' low-pay symbols have both a card rank and a suit on them, such as the jack of diamonds, the queen of clubs, the king of hearts, and the ace of spades. Up from them is a purple, green, and red monster. Clusters containing 5 matching symbols award players 0.2 to 2 times their stake, up to 100x to 5,000x for a 49-of-a-kind winning cluster. There are no wilds, but at random in the base game, so called fat symbols of 3x3, 4x4, 5x5, 6x6, or 7x7 may hit.
Book of Monsters: Slot Features
Hitting 4, 5, 6, or 7 scatters in the base game awards 5, 6, 7, or 8 free spins. If the ante bet is activated, then landing 3, 4, 5, 6, or 7 scatters awards 4, 5, 6, 7, or 8 free spins, respectively.
The next thing that happens is a random pay symbol is chosen as the Fat symbol for the bonus round. Players are given a choice to gamble the Fat symbol for a more valuable one. They can also gamble to increase the number of free spins. Or collect to start the feature. If you gamble for free spins or a better Fat symbol and the book reveals 'The End', then the bonus round ends right there. Otherwise, up to 8 free spins can be awarded from successful gambles, and up to the highest value symbol is possible.
The free spins round has a progressive feature involving a Fat symbol. At the start of the round, the 1x1 Fat symbol is always present on the grid, and it moves to a new position at every spin. All instances of the Fat symbol type that hit during the round, which are not overlapped by the Fat symbol, are collected by a meter. At certain collection thresholds, the Fat symbol grows in size. Collecting 30 symbols levels the Fat symbol up to 2x2, collecting 27 more makes it 3x3, collecting 24 more makes it 4x4, collecting 20 more makes it 5x5, collecting 16 more makes it 6x6, and collecting 12 more makes it 7x7. Each time the Fat symbol increases size 1-3 additional free spins are awarded.
Bonus Buy
The free spins bonus can be bought from the base game at a cost of 100 times the bet. When bought, 4, 5, 6, or 7 scatter symbols randomly land on the triggering spin.
Book of Monsters: Slot Verdict
The split second between noting the title and reading the rules or seeing the game in action was enough to assume Book of Monsters was going to offer yet more expanding special symbol action, Book of Dead-style. However, they say you shouldn't judge a book (or a 'Book of' slot) by its cover, and that piece of advice rings true in this case because it didn't take long to figure out Book of Monsters is not that sort of game. However, it is a bit like one of those TV episodes that was created by stringing together a bunch of short clips from past episodes. Like a clip show, a number of things about Book of Monsters stuck out from the past.
The first was the 'Book of' reference, and while this is a different style of game, books are used to award free spins and choose a random special symbol. Starting with 5 free spins is not a heck of a lot, so it might be quite tempting to try gambling up. During the test session, at least, 5 could be enough to level up the Fat symbol, though not all the way, so the more free spins, the better. And no, the Fat symbol is not wild, so again, gambling up to a more valuable Fat symbol might be tempting. Then again, lower paying symbols are arguably more prevalent on the grid, technically making increasing the Fat symbol easier than a low frequency higher paying symbol, so gamblers' preference there.
Not having a multiplier feature like Royal Potato and no growing wild like Fat Rabbit means Book of Monsters is in some ways limited. But it does have a win cap of 5,000x (equal to hitting a 7x7 version of the highest pay symbol), and the 1 in 547,945 frequency isn't a shocker. Book of Monsters is an unusual patchwork quilt of a slot, and the base game is a little dull, but growing a wandering Fat symbol is amusing enough to spare the game a look.
Book of Monsters' unusual mix of both familiar and surprising elements makes it worth a look.
