Game Information
Provider
SpinOn
Type
Slots
Theme
Halloween
Book of Evil Slot: Comprehensive Data Analysis
Core Game Specifications
| Attribute | Value |
|---|---|
| Developer | SpinOn (via Yggdrasil) |
| Release Date | September 18, 2024 |
| Theme | Horror, Gothic, Graveyard, Magic, Book |
| Layout | 5×3 |
| Paylines | 10 |
| Bet Range | €0.20–€50 |
| Core Mechanics | Random expanding symbols in base game, Expanding symbol in free spins, Book symbol as wild and scatter, Free spins bonus (10 spins), Bonus buy for 100× bet |
| Technology | Powered by Yggdrasil’s GATI toolkit |
| Program | Part of YGG Masters program |
Mathematical & Payout Model
Return to Player (RTP)
94.0% / 90.5% / 86.0%
Volatility
High
Max Win Potential
5000x
Symbols & Paytable Hierarchy
| Tier | Symbol(s) | Function & Value |
|---|---|---|
| Low Tier | 10, J, Q, K, A | Provides small, frequent wins to maintain gameplay. |
| Mid Tier | male characters, female character | Thematic items offering moderate payouts. |
| High Tier | priest, Book symbol | Highest paying symbols. Top hits available with full combinations. |
| Wild | Book symbol | Acts as a substitute / feature trigger per game rules. |
| Scatter | Book symbol | Triggers free spins / bonus round when enough appear. |
Book of Evil Bonus Features Mechanics
| Feature | Trigger | Initial Award | Core Mechanic | Enhancement/Retrigger |
|---|---|---|---|---|
| Random Expanding Symbol (Base Game) | Each spin | A regular symbol is randomly selected to expand if enough land | ||
| Free Spins with Expanding Symbol | 3–5 Book symbols | 10 free spins | One symbol expands throughout free spins when landing | Retriggers possible with more Book symbols |
| Bonus Buy | Player choice | 10 free spins | Direct purchase of free spins round |
Frequently Asked Questions (FAQ)
| What is the RTP of Book of Evil? | The RTP varies by operator and jurisdiction, with versions at 94.0%, 90.5%, and 86.0%. |
| Can I play Book of Evil on mobile? | Yes, the game is fully optimized for mobile devices with smooth performance. |
| How do I trigger the free spins feature? | Land 3, 4, or 5 Book symbols to trigger 10 free spins with an expanding symbol. |
| What does the Book symbol do? | It acts as both wild and scatter, substituting for symbols and triggering free spins. |
| Is there a way to buy the bonus? | Yes, you can buy the free spins bonus directly for 100× your bet. |
| What is the maximum win potential? | You can win up to 5000× your stake. |
| Does the expanding symbol appear in the base game? | Yes, a random symbol can expand in the base game if enough land. |
| What is the volatility level? | The game is high volatility, meaning wins are less frequent but potentially large. |
Book of Evil Performance Summary: Strengths vs. Weaknesses
Strengths
- Unique horror theme diverging from typical book slots
- Innovative expanding symbols in both base game and free spins
- High maximum win potential (5000×)
- Bonus buy option for direct access to free spins
Weaknesses
- Variable RTP includes low versions down to 86%, below industry average
- High volatility may deter players seeking frequent smaller wins
Overview
Book of Evil is a gothic horror-themed “book” slot developed by SpinOn in collaboration with Yggdrasil, released in September 2024. Set in a haunted graveyard, it features a 5×3 layout with 10 paylines, high volatility, and variable RTP (94.0%, 90.5%, 86.0%). The Book symbol acts as both wild and scatter, triggering 10 free spins and enabling randomly expanding symbols in both base game and bonus. A bonus buy option allows direct entry to free spins for 100× the bet, with a maximum win potential of 5000× the stake.
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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