Relax · Jun 11, 2026
Book of 99 offers massive 40,004x win potential paired with High volatility — high-risk, high-reward at its finest.
Looking for a High volatility slot with strong returns? Book of 99 by Relax delivers a 97% RTP with up to 40,004x your stake.
The slot draws inspiration from ancient civilizations and mythology.
Key features include Free Spins, Expanding Symbols and Wild Collection Meter.
プレイヤーは、その卓越した99%のRTPと高ボラティリティにより、フリースピンでの拡張シンボルを通じて最大12,075倍の巨額勝利の可能性を秘めたBook of 99を選びます。コレクションメーターは、ボーナスへの信頼性の高い、グリンドベースのルートを提供し、純粋な運よりも戦略的な持続性を好むプレイヤーにアピールします。
ワイルドコレクションメーターは、ベースゲームのスピンから99個のブックシンボルを蓄積し、スキャッターの着地とは無関係に自動的に10回のフリースピンをトリガーします。
Extreme volatility requires deep pockets — 600-1000x bet bankroll recommended for a realistic shot at the max win.
| Metric | Book of 99 | Bill Coin 2 | Bill Coin | Chip Spin |
|---|---|---|---|---|
| RTP | 97% | 97.32% | 97.32% | 97.29% |
| Vol | High | High | High | High |
| Max Win | 40,004× | 52,879× | 52,419× | 53,799× |
| Value | 85 | 87.3 | 87.3 | 87.1 |
RTP of 97% is +0.85% above the market average (96.15%), placing it in the top tier for player returns.
Max win of 40,004x is 5x the market median. This places it among the top 12% for win ceiling.
Maximum volatility, maximum reward ceiling
Value Score of 85/100 (top 14% of all slots). This combines RTP, volatility, and win potential into one metric.
Strong RTP paired with high win ceiling — the sweet spot between steady returns and big-win potential.
★★★★ 4.8/5 — 200% up to $1,000
★★★★ 4.7/5 — 300% First Deposit Bonus
★★★★ 4.5/5 — 100% up to €100
105 slots, avg RTP 96.86%
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Volatility More High volatility slotsBrowse all High volatility options
Rtp Top RTP slotsAll slots with exceptional return rates
| Provider | Relax |
| RTP | 97% |
| Volatility | High |
| Max Win | 40,004× |
| Hit Frequency | 15-20% |
| Math Profile | Balanced Power |
| Value Score | 85/100 |
| Risk Index | 5.6/10 |
| Win Potential | 9.2/10 |
| Bankroll Rating | 3.5/10 |
Book of 99 has an RTP of 97%, which is above average compared to the industry standard of ~96%. For every $100 wagered, the theoretical return is $97 over extended sessions.
Book of 99 has High volatility, meaning wins are less frequent but larger. Suits patient players with sufficient bankroll.
The maximum win potential is 40,004x your total bet.
Book of 99 was developed by Relax. Explore all Relax slots in our provider directory.
Book of 99 has a Value Score of 85/100, which is excellent. This score combines RTP, volatility, and max win into a single metric.
Many online casinos offer a demo mode for Book of 99 where you can play with virtual credits before wagering real money.
Book of 99 has a Risk Index of 5.6/10, making it moderate-risk. Relatively gentle on your bankroll.
| Bankroll | — |
| Return | — |
| Risk | — |
Whether you're chasing the 40,004x max win or enjoying the base game, Book of 99 offers a well-crafted slot experience.