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Book of 99

Book of 99 by Relax Gaming

There are so many Books of Blah Blah slots out there that it must be really hard and confusing for players who are looking for the best one to play. I wouldn’t say that Book of 99 from Relax Gaming necessarily is the best one because it will never be allowed for its intended purpose – bonus wagering.

Slots with a Return to Player (RTP) higher than 98% will immediately be added to the slots restricted from play with bonus money. That’s what the 99 refers to in the title of the game. It’s the RTP. Is there anything else then that makes this slot stand out from all the other slots with Book in its title?

Not really. At least not for me. I prefer games with high volatility and payout potential over slots that could grind your whole bankroll away, only slower. Still, I decided to review Book of 99 and I WILL do it, and hopefully we can both learn something from this.

Book of 99 – What you need to know

If you have ever played any Book of Blah Blah slot before, then you will already know how most of this stuff works. It doesn’t even matter which game studio is behind it, they pretty much play in the same way. The only thing that might be different is where the buttons are to adjust your bet. Here are my pros and cons for Book of 99.


  • Anyone who has ever played any Book of Blah Blah will know how the slot works.
  • 99% RTP, are you kidding me!?
  • Really nice intro.


  • The lack of originality is profound considering all the Book of Blah Blah slots out there.
  • Max win is 5,000x your stake.
  • 99% RTP, are you kidding me!?

Book of 99 – Theme and background

I think the theme is based on the Greek hero Odysseus and his journey home after the Trojan War. By the way, that horse they used to get into the city, his idea. Anyway, it took him 10 years to get home and during his travels he encountered all kinds of weird creatures like a Cyclops, man-eating giants, the Goddess Circe, Sirens and a whole lot more.

There are definitely symbols in the game that represents some of the creatures and people Odysseus ran into during his epic journey home.

Book of 99 – Gameplay

There are TWO ways to trigger the free spins feature. You can either hit 3 or more book symbols on the same spin, or you can collect 99 in total over time. There’s a boat journey to the left where you can follow your progress towards getting the free spins.

When free spins are triggered, the first thing that happens is that the Book of 99 reveals a random symbol which will be the important one during the feature. You will start with 10 free spins and as long as you hit at least 2 character or 3 card symbols they will expand to cover the entire reel and pay out on every payline (15) even if they aren’t next to each other.

If you manage to land 3 books during free spins you will get an additional 10 spins to play. As far as I know you can retrigger free spins limitlessly in theory.

One thing that’s worth mentioning is that the books collected aren’t reset to 0 if you hit 3 scatters. The 3 are simply added to the journey. This could lead to a couple of interesting possibilities that I haven’t taken the time to test because it would take too long.

What happens if you have collected 96 books and trigger free spins the normal way with 3 books? Does it mean that you get 10 free spins followed immediately by 10 free spins for collecting 99 books? I think so…

Book of 99 – My verdict

You may have noticed that I put the 99% RTP in as both a pro and a con, and for good reason. There are three massive problems with a slot like this. Firstly, not every casino will be offering this game because of its RTP even though it’s volatility is high.

Secondly, even if a casino will bring this slot into its library, you will never be allowed to play this slot when you’re wagering bonus money. Again, because of the insanely high RTP. There was a time when Blood Suckers by NetEnt (98% RTP) was used to abuse bonuses and that slot was quickly restricted from play with bonus money.

And lastly, new players who don’t even know how to break wagering requirements with high RTP slots may start playing this slot without noticing that they are only playing with real money and not bonus money, which may cause a lot of frustration and anger live chats with customer support agents (don’t ever do that).

As a gimmick, I will say that 99% RTP on a slot with high volatility is intriguing. And I like the added feature of collecting book symbols to trigger the free spins feature, unlike other Books of Blah Blah slots where you have to do it the natural way by hitting 3 scatters.

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