Book of 99 Slot

Relax Gaming has created a slot that combines two of the most popular themes in slots nowadays, the "Book of…" and the Ancient Greece theme. Such a combination means nothing but success ... Read Review

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Reviewed by Jim Tomlin

Slot Information

Slot Information

RTP: 99.00% Volatility: 3 Maximum win: $1,207,000.00 Progressive Jackpot: No Bonus Feature: Yes
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Book of 99 Review

Relax Gaming has created a slot that combines two of the most popular themes in slots nowadays, the "Book of…" and the Ancient Greece theme. Such a combination means nothing but success since Book of 99 slot is about to make a real boom across the industry.

You may not assume from the title right away, but the title is related to the mind-blowing RTP this game offers. Book of 99 offers a staggering 99.00% RTP, and that’s its strongest suit, and one of the main differences between it and its Play'n GO counterpart. Add to that the fact that the highly volatile slot comes with a pretty standard 10-payline, 5 reels grid, and you’ve got yourself an already exciting slot to play for real money. But, you should know that you’ll be showered with Free Spins and Expanding Symbols, as well as the Wild Collection feature, taking you to wins of up to 12,070x the stake. Ready to explore the Greek temples and meet the villains and heroes of the glory Ancient Greece days?

Meet Our Slot Tester

Jim Tomlin

Jim Tomlin

With more than 20 years of experience in online gaming and Sports journalism, Jim has keenly tested, played and reviewed a multitude of slot games, looking for characteristics that differentiate them in terms of themes, features and jackpots before they reach the market. When Jim finds a slot game he likes, he just keeps on spinning, going for the win. Not much we can do about that!

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Book of 99 Controls, Setup and Paytable

As mentioned, when you load Book of 99 slot, you will be both mesmerized and creeped out by the symbol design. Relax Gaming has done an outstanding job creating the symbols, using cartoonish graphics, yet designing them to leave you in awe. They are both scary and beautifully designed, so you can rest assured that you'll enjoy the slot, in terms of visual effects.

When it comes to the setup and controls, the reels are at the centre of the screen, presented on the wall of the temple. On the left side of the reels, on the temple’s pillar, you have the Wild Collecting Meter. On the right side of the reels, you see controls. First is the Quickspin button, followed by the bet configuration field, where you can place a bet from 0.10 to 100 credits. The Play and Autoplay buttons are next.

Next, you see the three-bar button, where the paytable is. You will see that the low-paying symbols are the playing card Royals, in Greek style, while the high-paying are characters, villains and heroes, from the ancient Greek stories. The high-paying symbols can deliver payouts from 75x to 500x the stake.

Finally, below the reels, going right to left, you see the Bet display, the Win display and the Balance display.

Book of 99 Mobile Slot

Relax Gaming always makes sure you get to play its slots across all devices. To do that, it uses the HTML5 format for all of its slots, making them playable across all Android and iOS devices.

Therefore, regardless of whether you have a Samsung or an iPhone, or any other smartphone or tablet, you can rest assured that Book of 99 will play interruption-free on any device.

Slot Features

  • Scatters

  • Wild symbol

  • Free Spins

  • Stacked symbols

  • Quickspin

  • Retriggering

Book of 99 Base Game Features

There are few things you need to know about the base game of Book of 99. The Book symbol is the Wild, which substitutes for all symbols bar the special Expanding Symbol during the bonus game. There's much, much more to this slot machine than the free spins bonus though.

You should also know that any time you land this symbol, it gets collected on the left side of the reels, in the Wild Collection Meter. Collecting 99 Wilds, you will trigger the bonus game. Should you trigger the bonus game this way, it will be played with a bet size corresponding to the average of the bet sizes used when collecting each Wild.

Book of 99 Slot Free Spins and Bonus Features

While you can trigger the Book of 99 bonus game by collecting 99 Wilds, you can also trigger it the easier way. You can trigger it by landing 3 or more Wilds, from left to right on adjacent reels, for which you get 10 Free Spins. So essentially, the Wild Collection feature will help you later retrigger the feature, since you’ll need time until you collect 99 Wilds, compared to landing only 3 or more Wilds to first trigger the bonus game.

Before the Free Spins start, the game will select a random symbol to become the special Expanding Symbol, much like in the classing Book of Dead Slot. Land the Expanding Symbol, and it will expand to cover the entire reel it landed on. Land more than one Expanding Symbol, and they will pay-both-ways, regardless of the lines they landed on, even if the symbols are not connected from left to right.

Book of 99 Max Payout

The most important part of Book of 99 real money slot is that it comes with an incredible 99.00% RTP. It cannot be stressed enough how important this is, since the slot will deliver a Return to Player percentage of 99.00%.

Add to that the fact that the slot arrives with a max payout potential of 12,000x the stake, and you’ve got yourself a winner! For the max bet of 100 credits, Book of 99 can deliver 1,207,000 credits! That’s right, it can make you a millionaire in a blink of an eye!

Book of 99 Slot Verdict

Book of 99 is an incredibly unique slot, truly worth the try. Its title does remind you of Book of Ra, but the slot is nothing like it. The design does remind you of the old Medusa series of slots. Relax Gaming has done an amazing job with the overall production. Yet, the star of the slot is the 99.00% RTP. This RTP is rarely offered by developers nowadays, so it is quite a refreshment. This 99.00% RTP paired with the 12,070x the stake max payout potential make Book of 99 the it-slot, the slot that could well become the next big thing. You can try it out at one of our top New Jersey online casinos and recommended Pennsylvania online casino sites for real money!

Book of 99 Slot FAQ

Do the Expanding Symbols appear if you trigger the Free Spins with the Wild Collection feature in Book of 99 slot?

Yes, indeed. Regardless of whether you trigger the Free Spins with 3 or more Book symbols, or you trigger it when you collect 99 Wilds, the Expanding Symbols will appear and the bonus game will operate under the same rules.

What is the best casino site to try out Book of 99 online slot?

You could join any Relax Gaming-powered online casino to play Book of 99 slot, but the choice would be entirely yours, as only you can decide which casino would be the best one for you.

Will I win real money prizes playing Book of 99 slot?

Sure. Book of 99 is available in both real money and demo play.

What is Book of 99’s RTP?

Book of 99 is officially one of the most rewarding slots since it comes with an RTP of 99.00%, which is an RTP that is rarely offered in other slots.

Should I always bet the max bet on Book of 99 online slot?

Your prizes will depend on your bet, therefore, betting the max bet would take you to the best prizes. But it is up to you whether you can afford to bet the max bet always.

What is the max payout Book of 99 can deliver?

Not only does it offer an RTP of 99.00%, but Book of 99 also offers a payout potential of 12,070x the stake. Therefore, for the max bet, it can deliver a massive 1,207,000 credits prize!

Do I need to download any software to play Book of 99?

No. Book of 99 is an HTML5 title, meaning it can be played cross-device, without the need of downloading any software.

When was Book of 99 released?

Relax Gaming released Book of 99 slot on the 4th of May, 2021.

Is Book of 99 a slot worth playing?

Definitely. If you’re looking for a “Book of…” or an Ancient Greece-themed slot with a high payout potential and RTP, Book of 99 is the slot to try.

Does Book of 99 offer a jackpot prize?

While there’s no progressive jackpot pool attached to it, Book of 99 does offer a max payout prize similar to a jackpot prize, of up to 1,207,000 credits!

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