Book of 99

Editor's rating:
star-iconstar-iconstar-iconhalf-star-iconstar-iconstar-icon
Published: April 20, 2021|Updated: April 21, 2021

Book of 99 Slot Review (Relax Gaming)

Book of 99 is a slot with 99% RTP from Relax Gaming.

Not only that but as the name implies, it’s based on the popular “book” slot concept (Book of Ra, Book of Dead, etc.). This of course includes the free spins bonus with a special expanding symbol. This time, however, it can also be triggered through a bonus collection feature that will keep track of your average bet as well. And instead of the Egyptian theme, the Book of 99 is designed around Greek mythology, helping it stand out a tiny bit more from a plethora of similar games.

Book of 99 is available at Relax Gaming slot sites like Rizk from 4 May 2021.

Play Book of 99 at Licensed Slot Site
Recommended Relax Gaming casino

Rizk
All-star signup bonus
Get 10 Free Spins or €/£/$25
Play here

No wagering requirements on this signup bonus. Rewards must be claimed within 7 days. No code needed. New 18+ customers only. Play responsibly. Full T&C apply.

99% RTP

Book of 99 has a theoretical average return to player of 99%. Such high RTPs are usually seen in table games but not slots, with a few exceptions like NetEnt’s Mega Joker (99%) or Thunderkick’s 1429 Uncharted Seas (98.5%)

The RTP in itself is not a perfect indicator of short-term wins or losses. In the long term, this translates into lower margins or house advantage for the operator/casino, by as much as four times when compared to slots with an average of 96% RTP. Theoretically, this should mean quite a bit in savings and extended gameplay for the players, but as we know human is not always rational, and far from that when choosing to play slots. This slot would be the most rational within the context.

Single-line wins can pay up to 500x with the best symbols.

Base Game

Book of 99 has 5 reels and 10 fixed lines. Symbols are also easy to track. There are 10 different icons that come non-stacked and that pay up to 500x for a single full line. The book symbol is both Wild and Scatter.

The hit frequency of 29.83%, which is relatively high to the 20% baseline in high variance slots.

👍 Tip: Some casinos limit bonus wagering on high-RTP slots, so Book of 99 will be the first one to be excluded if this is the case.

Free Spins with Special Expanding Symbol

Special expanding symbols pay in scattered positions too.

One way of winning 10 free spins is by getting 3 or more of the special Scatters/Wilds. Unlimited re-triggers are also possible the same way.

Once triggered, the bonus will shuffle from a deck of existing symbols to pick a special expanding symbol that will expand and pay scattered, according to the paytable. Getting the high symbol is obviously the best but it’s just as difficult to trigger any bonus wins with it.

The average win in the bonus is 68.8x, which is good considering the fact that you’ll get the free spins one or the other way within 15-minutes of play on average. Based on my experience, however, it is very rare when wins break the 200x barrier.

Bonus Collection

Only 1 special symbol is needed to make it expand on that reel.

The other way to win the bonus is by getting 99 Wilds/Scatters.

For every Wild symbol, the collection meter will move +1 and keep track of the bet amount that triggered it. Get to 99 to trigger the bonus spins, which will be played at the average bet. Here are some more useful stats:

  • Big Win probability (15x bet or more) – 1 in 108
  • Mega Win probability (30x bet or more) – 1 in 180
  • Epic Win probability (60x bet or more) – 1 in 305

For comparison, the probability of an Epic Win in Money Train 2 is 1 in 418.

👍 Tip: The average win in the bonus is 68.8x.

 

Conclusion

Editor's rating:
star-iconstar-iconstar-iconhalf-star-iconstar-iconstar-icon

It seems that the high RTP comes at the expense of very linear gameplay. Even though Book of 99 is played at high volatility, you can go for thousands of spins without deviating much from where you started with your balance. One way the more risk-prone players can add risk is with higher bets, which this slot accommodates very well having a flexible betting range of between 0.10 and 100 credits per spin. The high RTP provides quite a bit of safety, but it doesn’t make for the most interesting of slot sessions as bets above 200x are reserved for the best days. That is until against all odds you get one of the high symbols expanding during the free spins, which Relax Gaming claims to have simulated wins of over 12,000x bet.

While Book of 99 certainly has an interesting concept to complement the famous series, players expecting anything more than the good old “book” concept may be better off with Play’n GO another Book of Dead sequel called Rich Wilde and the Amulet of Dead, which just became available. For those of you who are concerned about Book of Dead’s RTP being lowered to 94% at some slot sites, Book of 99 with its fixed 99% RTP will be an interesting find.

Rizk
All-star signup bonus
Get 10 Free Spins or €/£/$25
Play here

No wagering requirements on this signup bonus. Rewards must be claimed within 7 days. No code needed. New 18+ customers only. Play responsibly. Full T&C apply.

About Our Reviews

Full disclosure: Mvideoslots.com is an affiliate site which provides free information about online slots, slot sites and everything related. Some of the links on this site are affiliate links, so we may earn affiliate commission from casinos when someone makes a deposit through our site.

Note: We have never and will never do paid reviews. This means that both the casinos and game developers are seeing the reviews when they are published for the first time, right alongside you. We do not send them the reviews for an early look, so everything we say is our honest opinion. Should we ever do a paid article, it will not be a “review” and we will make sure to mark it as a sponsored article or an “ad”.

Can you trust Mvideoslots.com reviews? I hope so, because at the end of the day I want you to be happy with the casino or slot that you choose. But I also encourage you to look at other trusted sites which may have different opinions. If you decide to look around then make sure that it is a trusted source because it is common practice for casino operators to have their own “review sites” which are biased, not to mention the sites which have reviews written by people who are not following the industry.

Now that you know how we run things here, thank you for your supporting independent sites like us. If you have any questions, just send me an email.

Nikita, Founder and reviewer at Mvideoslots.com.

Relax Gaming slot reviewsSee all

See more Relax Gaming slot reviews

96.25%
High
17,280x
96.40%
Very high
50,000x
96.83%
Very high
51,840x
See all
Recommended Relax Gaming casino
Rizk