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Book of 99 Slot Review

Min/Max Bet
0.10 / 100
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11 Free Spins + 100% up to €$200 Bonus
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18+ | 11 welcome spins valid on random game on 1st deposit. 7 days to activate bonus spins, once activated welcome spins must be used within 24 hours. No wagering on welcome spins winnings. No max cashout on winnings. 100% deposit bonus up to £200. £10 min deposit. 35x wagering before you can withdraw bonus funds. You can forfeit the bonus and take the winnings and paid out bonus funds. Bonus paid out in 10% increments. Max bet 50% of deposit up to £20. 30 days to activate, 60 days to complete the bonus. Play Responsibly.T&Cs Apply - 18+ | T&C's Apply
Casinos to Play Book of 99 Slot

One of the highest RTP slots online

With a high 99% RTP the Book of 99 slot game is one to keep an eye on thanks to Expanding Scatter Free Spins and a 5,000x your bet max win.

A 5 reel, 10 payline game, this is another ‘Book of’ slot that follows in the footsteps of the Book of Ra and Book of Dead.

This time though Relax Gaming are taking us into a mythical set of reels where you collect wilds to trigger free spins and enjoy what is a high variance slot machine with the potential for big wins.

Let’s find out what you can expect from the Book of 99 online slot and if that 99% RTP is worth playing for.

Book of 99 Wilds & Wins

There’s not much to this Book of 99 slot game.

You get a 5×3 reels slot filled with low paying A – 10 symbols and higher paying Mythical creatures.

In the base game you’ll find wins that are few and far between, with the occasional big win thrown in thanks to the Wild symbol, which substitutes for all other symbols.

Unlike other ‘Book of’ slots though you won’t find any Wild Scatters in the base game and you’ll also trigger the Book of 99 free spins bonus in 2 ways not one.

  1. Find 3 Wild Bonus Symbols on a single spin
  2. Collection Feature: collect 99 wilds throughout your spins

Here, every wild that lands on a spin gets added to the collection meter to the left hand side of the reels.

Reach 99 and your efforts are rewarded with 10 Free Spins.

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  • Software: Relax Gaming
  • Min Bet: 0.10
  • Max Bet: 100
  • Slot Type: Video
  • Paylines: 10 Paylines
  • Reels: 5 Reels
  • Slot RTP: 99%
  • Slot Variance: High
  • Free Spins: 10 Free Spins with Random Expanding Scatter Symbol
  • Wilds: Book is Wild and subs for all others except expanding symbol in free spin
  • Other Bonus Games: Collection Feature
  • Mobile: Yes
  • Slot Themes: Myths & Legends
  • Release Date: April 2021
By SlotSumo | Updated: Jun 13th 2021 | Rating 4.0

Book of 99 Free Spins with Expanding Scatters

The feature that you’ll most be looking forward to triggering early is the Free Spins bonus round.

Do this in either of the two ways we mentioned above and you’ll receive 10 free spins.

The free spins from triggering with 3 wilds are played at your current bet level, while the free spins triggered by collecting 99 wilds is payed at an average bet size for every time a wild was added to the collection meter.

A bit strange but it could provide you with bigger wins if you’ve used slot strategies that increase or decrease your bet size.

Once triggered, a symbol is chosen at random to act as an expanding scatter symbol, paying when 3 or more are on different reels.

It’s a feature we’ve seen many times before, many of times in the Play’n GO Rich Wilde slots and similar ‘Book of’ games.

It adds thrills, but don’t always expect to win big. While playing this slot to write this review our free spins wins varied from anywhere between 20x and 100x our bet, but with a 5,000x single spin max win available there’s plenty more available from this game.

Slot Review Conclusion: Big RTP but lacks the thrills

The key focal point that many slots players will look at when they hear about the Book of 99 mobile slot and online game is the huge and rare 99% RTP.

Just cause a slot has a high RTP doesn’t mean that you’re always going to win. This is a high volatility slot after all, where wins can be few and far between so budget your casino cash wisely fi you want to experience all that this game has to offer.

Which is a fun game, but lacks the base game thrills of games of its type.

Overall if you’re after a new slot to play that has a few good features and an enticing 99% return to player rate then by all means give it a spin.

It looks good and sounds good and get a lucky free spins round early and you could be walking away happy.

A good addition to the Relax Gaming slots collection which has a proven set of big win online slots.

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Get your 11 Free Spins + 100% up to €$200 Bonus at Videoslots Casino T&Cs Apply 18+ New Players Only

Relax Gaming Book of 99 Slot Logo
Book of 99 Review
  • By Relax Gaming
  • RTP: 99%
  • 5 Reels, 10 Paylines
  • Min Bet: 0.10
  • Max Bet: 100
  • 2 ways to trigger the Free Spins
  • High 99% RTP
  • Free Spins with Expanding Scatter offer biggest wins
  • Win up to 5,000x your total stake
  • Play at Relax Gaming casinos online & mobile

Book of 99 Slot FAQs

What’s the Book of 99 RTP?

Like the name might suggest the Book of 99 RTP is 99%, which is one of the highest RTPs online.

What is the maximum spin win?

The Book of 99 max win is 5,000x your total stake, which can be achieved in the Free Spins bonus thanks to Expanding Scatters.

Is there a Book of 99 free play demo?

You can play this video slot for free before playing for real money thanks at most casinos with Relax Gaming slots.

Is there a Book of 99 mobile slot?

Yes, you’ll find Book of 99 on our online mobile slots list and it’s available to play on your Android mobile, tablet, iPhone or iPad.

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