Released: 4 May 2021

Let’s spin the reels like it’s 1999 and fight the big Cyclops in the latest adventure from Relax Gaming called Book of 99. Of course, we won’t go back to the technology of the 90s; we were keen on just using the Prince’s phrase from the song there. This Greek themed adventure comes with a free spins bonus game and an expanding symbol that fills the entire reel whenever it lands. But, we save the best for last. Are you probably assuming that this slot game comes with an excellent RTP ratio of 99%? If yes, then you’re right. Test and explore the win opportunities in our detailed Book of 99 slot review below.


Book of 99 Slot

Book Of 99 Slot Review

At times when there are so many “Book Of” themed slots out there, it is really a challenge for developers to introduce something that’s already seen. Still, with a creative twist and following the pattern, Relax Gaming has released Book of 99, a title that’s pretty standard in terms of design and gameplay. But, don’t judge the book by its cover, they say, as this one will surely cause a lot of attention across players’ slot communities.
Apart from the generous RTP of 99%, the Book of 99 slot introduces special expanding symbols and a wild collectable bar. These features can all trigger the free spins bonus game, which we’ll explain in short. As you can already see, the book plays a vital role in the reel action of this slot game, but that doesn’t mean that other symbols don’t have their minutes of fame on the grid. Stay with us as we cover every detail of this potential slot hit.

About Book of 99 Slot 

The Book of 99 slot by Relax Gaming is a blend of historical and mythological elements inspired by Ancient Greece. It is played on a classic 5x3 machine that offers 10 active paylines throughout spins. To form a win, you’ll need at least 3 matching symbols on a payline, starting from the leftmost reel. The main action in this slot game revolves around the book symbol, as it plays the expanding wild and the special collectable symbol.

Before you start exploring Book of 99’s features, make sure your bets are aligned in the range from £0.10 to £100 per spin. This level is suitable for both beginners and more experienced players, as it’s suitable for all pocket sizes. Use the + and – buttons so you can adjust your bet preferences.
The best opportunities to win a big prize come from the bonus round, as you may already expect. The maximum win of the Book of 99 slot is set at 5,000x your bet. Moreover, the symbols have the power to deliver up to 500x your stake. Talking about symbols, let’s explore the paytable and overall graphic design of the theme.

Design, Symbols and Graphics

The Book of 99 slot is set across a classic, ancient-themed reel temple framed with marble columns. The action happens in the night time, as to why the overall atmosphere is dark with dominant blue, purple and grey colours. Overall, the design is of high quality, and the visuals are presented in a rather comic style. The mysterious ambient sounds in the background perfectly fit the overall mood.
On the reels, you’ll see A-10 royals joined by higher value symbols of cyclops, female and male warriors and Lamia, a mythological monster. As you already know, the book is the symbol that plays a dual role during gameplay, as it acts as a wild and collectable symbol. If you’re lucky to align 5 premium symbols, you’ll boost your total with a win starting from 75x and going up to 500x your bet.

RTP, Variance and Payouts for Book of 99 Slot 

The Book of 99 slot’s RTP is 99%, and you certainly don’t come across many slot games with an RTP that are exceeding the average levels. Call it a marketing trick or a great selling point; you don’t see this often in slots inspired by the “Book Of “ concept. The variance is high on the scale, meaning you’ll get the best chances to win big during the bonus game. The maximum win in this slot is set at 5,000x your bet, which is decent.
On the other hand, the hit frequency rate of nearly 30% signals that almost a third of the spins will be winning ones. However, don’t take this info for granted, as this is based on tests that involve millions of spins, and the situation may vary as it’s based on randomly triggered events. If you want to read more about RTP and variance models, check out our detailed Variance, Volatility and RTP guide and see which one suits you best.

Gameplay and Features on Book of 99 Slot 

As you may expect, the bonus features in theBook of 99 slot are pretty simple and straightforward. Every trigger and extra feature leads us to the free spins bonus game, and there are two ways to activate this feature. Let’s see how.


Free Spins

As soon as you land 3 or more wild book symbols across the grid, you’ll activate the Free Spins feature and win 10 free spins. Before you start spinning the reels for free, the game will choose one random symbol to be the special expanding symbol during these spins. If a special symbol lands on the reels, it expands and fills the whole reel. Here expanding symbols don’t have to be connected to form a win.
If you manage to get a full screen of male explorer characters, you’ll win the maximum prize for this slot game, capped at 5,000x your bet. Moreover, landing 3 or more wilds will retrigger the feature, giving you another round of 10 free spins. The developer says that there’s no limit to retriggers, which is good to know.
The second way to trigger the free spins game is via the Collection feature. You’ll see that each wild symbol is collected in a special bar from the left side of the reels that gets you closer to the treasure map. If you collect 99 wilds during gameplay, you’ll trigger the free spins round. Everything works exactly the same, just like the standard trigger option. Once you spin your 10 free spins, the metre resets and takes you back to the base game.

Book of 99 Slot on Mobile 

The Book of 99 slot is optimised to work on all mobile devices. Even though the reel set comes as quite unusual for a slot game, it loads and lands perfectly on any mobile screen. The developer has built this game with HTML5, which makes it adjustable on any operating system.

Other Relax Gaming Slots

Relax Gaming’s slots are known for their high-quality graphics, engaging gameplay and seamless user experience. Here, we’ll outline a few of our recent favourites, so feel free to check them out if something catches your eye.
The first on our list is the moustached Wild Chapo that loves to play with dynamite across the wooden reel set. The bonus pack of colossal and expanding wilds, re-spins and free spins reveal a prize of 10,000x your stake.
Have a smooth sail with the Sails of Fortune slot and join the crew on their quest to find the treasure worth 62,208x your bet. This high win potential is powered by the win ways, as they go up to 7,776 during the bonus round.
In the end, here’s an Irish-themed slot packed with superb visuals, lucky re-spins, and free spins called Emerald’s Infinity Reels. Powered by the famous Infinity Reels mechanic, the reel action can lead you to payouts of up to 10,000x your bet.

SlotsWise Verdict 

The Book of 99 slot is a great option to test the RTP model and maximise your chances of returning the investment. Relax Gaming understands that if you want to introduce a new “Book Of” themed slot, you have to give something new to the audience, and that’s the amazing 99% of RTP and simple but engaging bonus features.

The key to big wins hides in the bonus game section, where you can align the special expanding symbol of the highest value, and that’s the male explorer. In the end, it would be great to see the audience’ reaction to this game, and who knows-maybe other slot developers will be encouraged to go beyond that average RTP ratio.

Discover the Book of 99 slot by claiming a welcome offer right from this page and play at top-rated online casinos.

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