Book of 99
About this game
Book of 99 — Why This Slot Has 99% RTP
Book of 99 deliberately carries the industry’s highest RTP in its name. At 99.00%, Relax Gaming designed this as a statement — a Book-of-style slot that mathematically returns more to players than any competitor.
RTP 99.00%. High volatility. 10 fixed paylines on a 5×3 grid. Max win: 5,000x.
Wild Collection — A Different Way into Free Spins
Unlike traditional Book-of games that rely on Scatter symbols, Book of 99 uses a Wild Collection meter:
- Every Wild (golden book) that lands fills the meter.
- Collect 99 Wilds = 10 Free Spins with one Expanding Symbol.
- Collect 99 more (198 total) = 12 Free Spins with two Expanding Symbols.
This system makes bonus entry more predictable — you can see the meter filling and know roughly when Free Spins will trigger.
Free Spins — Expanding Symbols
When Free Spins activate, one symbol is randomly chosen as the Expanding Symbol. If it lands and can form a win, it expands to cover its entire reel. In the second round (two Expanding Symbols), both symbols can expand simultaneously for larger payouts.
What to Know Before Playing
- 99% RTP is a long-term average. Short sessions can still produce significant swings due to high volatility.
- 10 paylines only. This is not a feature-dense modern slot — the value is in the RTP, not the complexity.
- 5,000x max win is modest compared to Money Train or Iron Bank, but the high RTP compensates over time.
