Book of 99

This new game from Relax Gaming has everyone buzzing. For this 'Book of' instalment, you'll be heading to Ancient Greece where the volatility is high and the RTP is even higher! Will the 99% RTP help you get some big payouts or will they remain as mythological as these Greek Gods? Review by Arram Bekarian.
rating Rating
3.5
rating Provider
Relax Gaming
rating RTP
99
rating Paylines
10
rating Volatility
High
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Book of 99, from Relax Gaming, as the name suggests, is another game in the series of countless ‘Book Of’ titles that have been published from a variety of developers since Novomatic began the trend back in 2004 with Book of Ra. Despite sounding like just another slot to jump on the ‘Book of’ train, however, this one has a few twists. This gem, with its super-high RTP rate, is perfect for players looking to churn through bonus wagering requirements.

Read on for the full review.

SLOT FEATURES High RTP, Free Spins, Secondary Free Spins Trigger, Special Expanding Symbol
RELEASE DATE 4 May 2021
GAME PROVIDER Relax Gaming
SLOT TYPE Video Slot
THEME Mythology
REELS, ROWS, PAYLINES 5 Reels, 3 Rows, 10 Paylines
BET LEVELS 0.10/100
MAXIMUM WIN 5,000x Your Stake
SCATTER SYMBOL Yes – Book
WILD SYMBOL Yes – Book
BONUS GAME No
FREE SPINS Yes
RESPINS No
MULTIPLIERS No
JACKPOT No
RETURN TO PLAYER 99.00%
VOLATILITY Very High
Book of 99 slot screenshot of the reels

Book of 99 Review

If you know how a ‘Book of’ game usually works, then the meat and potatoes of Book of 99 won’t shock you. In fact, the paytable symbol count and prize groupings and its Free Game feature are identical to Book of Ra. No points for originality there. However, the aptly named Book of 99 comes in with an RTP of 99.00% and is coupled with a secondary trigger into the Free Games with a 99 BOOK collection mechanic.

It is also refreshing to see a ‘Book Of’ game move away from the typical ‘Treasure Hunters pillage Ancient Egypt’ theme.

Let’s get into it.

Features

Natural Trigger (Primary)

Collection Trigger (Secondary)

  • Win 10 Free Games after 99 BOOK symbols are collected. Free Games are played at the average of the bet sizes used when collecting each BOOK.

In the unlikely event of a simultaneous trigger, where both primary and secondary triggers occur on the same spin, two slot features will play back-to-back, beginning with the primary trigger.

Free Games:

After triggering Free Games;

  • One of the 9 regular symbols is randomly chosen to be the Special Symbol for the duration of the feature.
  • For each spin, any normal wins are paid out first. Then, if there are enough of the Special Symbols (2 for high paying symbols and 3 for low paying symbols), they expand to cover the whole reel and pay out for each of the 10 lines, and pay as Anys. This is standard ‘Book Of’ behaviour.

Paytable Review

As previously mentioned, the paytable is identical to Book of Ra, well, almost identical. Because of the secondary trigger, where there is no such primary trigger of 3-or-more scatters, Relax has removed the trigger win to be fair to Free Games triggered via the collection mechanic. The RTP from the scatters won’t be too high, but it still gives mathematicians some leeway to improve other areas of the game.

Playability

Playability is great. Hat’s off to Relax for creating a slick, high paced game. The gameplay action, the attention to detail, the snappiness, the slight delays when certain events occur, the subtle sounds and event recognition elements are among the best we’ve seen in the industry.

There are two main pillars in this game. The high RTP and the secondary trigger.

Expect the combined feature hit rate to be around 140 spins when evaluated together. Separately, expect to collect 99 scatters across 269 games while the primary trigger (with three or more scatters) comes in at around 294. As these separate triggers enter into the same feature, the RTP from the collection trigger will be slightly higher to round up the value of the additional bets required to hit the feature from the primary trigger.

So, where has Relax added its 4% over Book of Ra to get to the impressive 99%? The removal of scatter pays actually reduces RTP so now we have approximately 5-6% to look for. The remaining prize values are identical; so not there. Relax may have boosted the hit frequency of the higher paying symbols but, this looks unlikely judging by the 50% RTP rate in the base game. It is more likely Relax has increased the probability of higher paying symbols being selected as the Special Symbol in Free Games, giving players a nicer run through the feature, especially now that there is greater emphasis on Free Games with the secondary trigger.

The Glory Spin

The Glory Spin is in the Free Games feature. The WARRIOR symbol must be chosen as the Special Symbol then one per reel needs to land. The top award of 500x across 10 lines becomes 5,000x. This however is not capped, so Free Games will continue if the max win is hit. Relax claim their highest simulated win across an entire feature is 12,075x.

Delights and Surprises

  • The high RTP.
  • The secondary trigger.
  • The high production quality.

Shortcomings

  • Using an unimaginative ‘Book Of’ engine as the host game.

Conclusion

Great to see a well-choreographed game amongst the mediocrity being released of late. There is some simplicity in the surrounding artwork that help emphasise, and focus attention, on key areas of the game. What will be interesting to see is how operators treat Book of 99. Typically, operators reject such games, stating their risk is too high, or ask for liability guarantees from the developer. Will they exclude it from free rounds or other welcome bonuses due to its high RTP? For a player, it’s a gem of a game to churn through bonus wagering requirements.

The reelspin at 2.4s is quicker than some jurisdictions allow and I’d expect the version released in the UK will be running its minimum 3.0s reelspin.

I wonder (and quietly hope) if Book of 99 is openly embraced by operators, will it open doors for other developers to follow suit and release more fantastic high RTP slots?

Book of 99 gets 81 Spins out of 100 based on the following ratings:

PLAYABILITY 95
ORIGINALITY 20
BUILD QUALITY 100
MARRIAGE 80
IMMERSION 95
RUN FOR MONEY 90
INTEGRITY 95
TOTAL 82

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