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Book of 99 review
Greek myth or fable?
The ancient Greek theme is appealing, and the high RTP of 99% is attractive, but it’s clear that the moral of this story is patience when it comes to seeing wins.
Book of 99 symbols and payouts
The symbols are a mix of characters from mythology and the playing card values that have been given an ancient Greek makeover. The low-value symbols 10, J, Q, K and A pay out 0.5x to 15x your bet. When heroes and mythological creatures land, you get 0.5x up to 500x your bet. The key difference is you get payouts for two or more on a payline instead of the three required for low-paying icons.
Book of 99 special features
By now, you’ll have spotted that this isn’t just a slot, it’s an odyssey. Fortunately, the journey won’t take years, or at least we hope not. We played the game to check out what the meter by the side of the reels does and whether it’s worth waiting for.
Book wilds
This is a ‘Book of’ slot, so of course, we were expecting something from the book symbol. In this game, it’s pivotal for a number of reasons. It acts as the wild, substituting for the paying symbols, although not the expanding symbol that we’ll explore later.
It also acts as the scatter, so three on the reels trigger the free spins bonus round. That’s not the only way to get free spins, though. That’s where the meter and the other part of the slot’s name come in. When a book lands on the reels, it fills up the meter, moving your boat, or trireme if you’re into historical accuracy, along its path. When you collect 99, the free spins launch.
Free spins
We’ve already laid out the importance of the book symbol and how it leads to free spins in two ways. However you get there, you’ll get 10 free spins. Before the round starts, one of the icons is randomly selected to be the expanding symbol.
It expands when it lands on the reels, meaning you could get payouts across all 10 paylines. If they don’t cover all of the reels, you still get your normal payouts plus any expanded payouts, and they don’t have to connect from left to right.
Almost a Herculean task
Seeing 99 books land isn’t quite an impossible task, but it feels like you need the Graces, the Muses and the Greek Gods on your side to get to the free spins rounds. Of course, seeing three land together is a shortcut, but it seemed just as unreachable during our gameplay.
Book of 99 graphics & sound
It’s not easy to put your finger on what ancient Greece should sound like, but this slot does a decent job. It’s a bit mystical and fairly soothing while also building tension. The meter that turns golden as it fills and the temple framing the reels are a nice touch, too.
| Graphics | 3D |
| Optimised for Mobile | 👍 |
| Music | A decent attempt at the sound of ancient instruments |
| Special features | Roars from a Cyclops and other mythological twists |
Book of 99 Mobile Experience
During our initial Book of 99 review, we played the desktop version. However, we also took it for a spin on Android and iOS devices. It worked just as well on our phones, keeping everything in view.
No need to consult the oracle
We’ve left no stone unturned by testing this slot on our phones. The colour scheme for the base game is a little dark, but the play experience is pretty good.
Book of 99 Pros & Cons
Another Greek saying that we stand by is to call a spade a spade, or a fig, as it were. That means looking at the downsides as well as the positives, which is why we’ve listed the pros and cons.
| Advantages | Disadvantages |
| ✅ 99% RTP | ❌ Bonus round doesn’t trigger often |
| ✅ Expanding symbols for improved payouts | ❌ High volatility means patience is required |
| ✅ Payouts for just two matching high-value symbols | |
| ✅ Detailed Greek mythology theme |
Even Greek warriors have an Achilles heel
While the features of this game are appealing, we have to point out that they don’t come around often. With this pace, how much fun you have will depend on your bankroll and need for action.
Best online casinos to Play Book of 99 in the UK
A trip to Greece sounds nice, but it’s not necessary for this slot, as you can find it at these UK casinos.
Solutions to issues with the game
Just like Odysseus, you might hit a few snags on your journey. With the right solutions, you’ll be on your way in no time.
- If the game is interrupted, refresh to resume your progress.
- Since you’re collecting symbols for the meter, you should pick up where you left off. If you don’t, we definitely recommend informing the casino via customer support.
Not quite the midas touch
By the end of our Book of 99 review, the slot had lost its shine a little. The 99% RTP seems great, but the reality is that being a high volatility slot means you need patience to see action and any return. We’re not totally against that, but it won’t suit every bankroll.
Slots to try if you like Book of 99
The good news is that this isn’t the only slot with 99% RTP. UK players can also check out these titles.
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