Game Information
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Provider
Relax Gaming
Type
Slots
Theme
Book of
Reels
5
Min Bet
0.01
Max Bet
10
Max Win per Spin
500000
Book of 99 Slot: Comprehensive Data Analysis
Core Game Specifications
| Attribute | Value |
|---|---|
| Developer | Relax Gaming |
| Release Date | May 4, 2021 |
| Theme | Ancient Greece, Mythology |
| Layout | 5×3 |
| Paylines | 10 |
| Bet Range | €0.10–€100 (or equivalent) |
| Core Mechanics | 99% RTP, High volatility, Collection meter for free spins, Expanding symbol in free spins, Retriggerable free spins |
| Technology | HTML5, mobile‑friendly |
| Platform | Desktop, tablet, mobile |
Mathematical & Payout Model
Return to Player (RTP)
99%
Volatility
High
Hit Frequency
29.8%
Max Win Potential
12075x
Symbols & Paytable Hierarchy
| Tier | Symbol(s) | Function & Value |
|---|---|---|
| Low Tier | 10, J, Q, K, A | Provides small, frequent wins to maintain gameplay. |
| Mid Tier | Lamia, Cyclops, Pythia | Thematic items offering moderate payouts. |
| High Tier | Apollo/Odysseus hero | Highest paying symbols. Top hits available with full combinations. |
| Wild | Book (Wild/Scatter) | Acts as a substitute / feature trigger per game rules. |
Book of 99 Bonus Features Mechanics
| Feature | Trigger | Initial Award | Core Mechanic | Enhancement/Retrigger |
|---|---|---|---|---|
| Free Spins | Collect 99 Book Wilds or land 3 Book symbols | 10 free spins | Random symbol expands to fill reels during free spins | Retriggerable by landing 3+ Book symbols |
| Collection Meter | Each Book Wild in base game | Meter fills to 99 to trigger free spins |
Frequently Asked Questions (FAQ)
| What is the RTP of Book of 99? | The RTP is 99%, one of the highest in online slots. |
| How do I trigger free spins? | By collecting 99 Book Wilds via the meter or landing three Book symbols. |
| What is the maximum win? | You can win up to 12,075× your bet. |
| What is the volatility? | The game is high volatility. |
| What does the expanding symbol do? | In free spins, a randomly chosen symbol expands to fill reels and pays anywhere. |
| Can free spins be retriggered? | Yes, landing three or more Book symbols during free spins retriggers the round. |
| What is the bet range? | You can bet from €0.10 up to €100 per spin. |
Book of 99 Performance Summary: Strengths vs. Weaknesses
Strengths
- Exceptionally high RTP
- Engaging collection mechanic
- High max win potential
- Mobile‑friendly design
Weaknesses
- High volatility may deter casual players
- Theme similar to other “Book of” slots
Overview
Book of 99 is a high-volatility Greek mythology–themed video slot by Relax Gaming, featuring 5 reels, 3 rows, and 10 fixed paylines. It boasts an exceptional 99% RTP and offers two ways to trigger free spins: collecting 99 Book Wilds via a meter or landing three Book symbols. During free spins, a randomly selected symbol expands to fill reels, enabling wins up to 12,075× your bet.
Rachel Pine is our slots expert who has worked in the online gambling industry for 10+ years. Over the course of her career, Rachel has reviewed more than 30,000 slots.
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