lll▷ BOOK OF 99 SLOT GAME REVIEW 🌷

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BOOK OF 99

🎰 Full Review of Book of 99 Slot

📜 Game Overview

Yes, you are reading it correctly! We have made no mistake regarding writing down 99% being the RTP of Book of 99 slot!

This modern videoslot was released by Relax Gaming on 4th May 2021, and is one of the very few record breaking slots to offer a potential eye-popping 99% return to player. This certainly makes the game stand out of the competition, but the game developer has gone also further from that by producing a superbly designed 5 reel, 10 paylines videoslot.

Book of 99 slot is inspired to ancient Greece, but it's impressive design and soundtrack makes it a technologically advanced modern game from all points of view.

Developer: Relax Gaming
Relax Gaming is known for innovative, high-RTP games, and Book of 99 is a strong entry in the "Book of..." slot genre.

RTP (Return to Player)

RTP: 99%
This is exceptionally high for an online slot (industry average is around 96%). Book of 99 is one of the very few games that offers such a player-favorable RTP.

How to Play Book of 99 Slot

Set Your Bet: Choose your stake, usually from €0.10 up to €100 per spin.
Spin the Reels: Click spin and wait for symbols to land. 5 reels, 3 rows.
Winning Combinations: Match 3+ symbols left to right on paylines (standard "Book of..." mechanics).
Wild/Scatter Symbol: The Book is both the Wild and the Scatter.
- 3+ Books trigger Free Spins.
- During Free Spins: A random special expanding symbol is selected, which can expand across reels and pay anywhere.
Collection Feature: Collect 99 books during base gameplay to automatically trigger Free Spins without needing 3 Scatters in one spin.

To benefit from the abundance of FREE spins that are usually released while playing this high-paying slot game, you simply need to land 3 wild books. This is a wild that substitutes all other symbols, and that can trigger an unlimited number of free spins that can lead to a massive x5,000 your bet! The stakes range from a minimum of 0.10€ to a maximum of 100€ per spin. It is therefore easy to imagine what could happen if a high roller player triggers a high-value bet that is then multiplied by 5,000. In any case, the usual hit frequency rate that gives a winning combination is 29.83% which means a third of the bets will always release a winning combination.

Of all the available symbols, the male symbol is the most rewarding of all, that if lined on a payline can pay from x1 to x500 times your bet.

✅ Pros

Ultra-high RTP (99% — almost unheard of).
Guaranteed bonus via collection feature (no dependence purely on luck).
Massive Win Potential in free spins (especially if a high-paying symbol is chosen).
Beautiful Greek mythology theme with stylish graphics and epic soundtrack.
Low to medium volatility compared to some "Book of" slots, making balance last longer.

❌ Cons

Free Spins can be underwhelming if you get a low-paying special symbol.
Takes time to collect 99 books (unless lucky with scatters early).
No Buy Bonus Option — you must spin for Free Spins.

🎯 Why Play Book of 99 slot machine?

If you want the best theoretical odds in online slots.
If you like steady, less brutal gameplay with consistent base hits.
If you're a fan of "Book of..." style slots but want a less volatile experience.
Collectors and grinders will love the 99-book bonus system.

🧠 Tips for Winning at Book of 99

Aim for the Collection Bonus: Even if you’re not hitting scatters naturally, the 99-book system guarantees free spins eventually.
Play with lower bets if grinding: Keeping your bet size low lets you stay in the game longer, increasing chances of multiple Free Spins rounds.
Take advantage of the high RTP: Don't rush — let the RTP work for you over longer sessions.
If a low symbol is picked in Free Spins, hope for full-screen expansions: Even low symbols can pay well if they expand across all reels.

💶 How to win at Book of 99 slot with a €100 bankroll

Here's a specific plan if you have €100 to play:

1. Bet Size

Bet €0.50 per spin — this gives you 200 spins (€100 / €0.50).
It's a sweet spot between longevity and meaningful wins.

2. Objectives

Reach at least one 99-book collection to trigger Free Spins.
Try to trigger natural Free Spins during normal spins too.

3. Session Management

Target session time: Play for 45 minutes to 1 hour. Relax Gaming’s slots tend to play better over longer runs.
Monitor your book collection counter: Prioritize finishing collections before cashing out.

4. Cashout Philosophy

After a successful Free Spins round (300%+ return on initial bet size, e.g., win €150 from €50 invested): strongly consider cashing out or halving bet size to lock profits.
If you dip to €40 remaining without bonus: lower your bet to €0.20 to stretch the balance.

⚡ Important: No slot strategy guarantees wins. Slots are RNG-based!

CASINOS WHERE TO PLAY THIS SLOT

Please remember that while strategies can enhance your gaming experience, slot outcomes are ultimately determined by random number generators, and there's no guaranteed way to win. Play responsibly.