Free slot demo · player guide
Book Of 99
Relax Gaming rewrites history in Book of 99, where players battle amongst the gods in a first-of-its-kind 99RTP 'Book of' slot! Collecting 99 books in the Base Game triggers 10 free spins, an added route to the typical 3-symbol trigger.
18+ · free play · no account or deposit
Game details checked 21 Aug 2026How we check games
60-second guide
What matters at a glance
Free play
Play Book Of 99 here
Open the game below to check its pace, controls and features. Free play stays on SlotsCollector.
No sign-up · no deposit · full screen available
Look for
Features worth trying
- Game features
Book Collection Trigger, Expanding Symbols, Free Spins, Retrigger
Game overview
What is Book Of 99?
Relax Gaming rewrites history in Book of 99, where players battle amongst the gods in a first-of-its-kind 99RTP 'Book of' slot! Collecting 99 books in the Base Game triggers 10 free spins, an added route to the typical 3-symbol trigger. In this Greek odyssey warriors are welcome, one is chosen at random before heading into the ancient empire in the Bonus Round. Once the mythical character is chosen, it gains expanding abilities in the Free Spins round, growing to fill the whole reel and catapulting win potential up to 5000x one’s bet! Wins may not be set in stone, but the potential certainly is - when 3 or more book symbols land in the Bonus Round, 10 free spins are re-triggered, sending win potential soaring once again. Don’t judge a book by its cover, this ‘book of’ game is unlike the others. Get your players spinning, Midas touch could be within reach!
How it plays
The features that shape the game
Book Of 99 is listed as a Video Slot from Relax Gaming.
Game features
Book Collection Trigger, Expanding Symbols, Free Spins, Retrigger
Before you play
Does Book Of 99 match what you want?
Judge the format and features first. Theme alone tells you very little about how a game feels.
What this game offers
- Video Slot format from Relax Gaming
- High volatility
- Game features
What to check first
- This page lists RTP at 99%; confirm it in the version you open.
- Casino stake limits and feature settings may differ from the free-play version.
- Free play shows the mechanics, but it cannot predict a future result.
Quick answers
Book Of 99 FAQ
Clear answers based on the game information and demo status available today.
Can I play Book Of 99 for free?
Yes. Select “Play free demo” to open Book Of 99 on this page without an account or deposit.
What type of game is Book Of 99?
Book Of 99 is listed as a Video Slot from Relax Gaming. The confirmed features are listed above.
What is the RTP of Book Of 99?
The RTP shown for Book Of 99 is 99%. A casino may offer a different configuration, so confirm the value in the in-game information screen.
Can I play for real money here?
No. SlotsCollector provides game information and free demos only; it does not accept bets or deposits.
Game facts
Book Of 99 numbers and features
These are the details currently confirmed for this game. Check the in-game information before using real money.
Payouts & risk
- RTP
- 99%
- Volatility
- High
- Maximum win
- 12,075×
- Bet range
- €0.10 – €100
Reels & wins
- Reel layout
- 5×3
- Payout system
- Payline
Bonus features
- Features
- Book Collection Trigger, E×panding Symbols, Free Spins, Retrigger
- Bonus buy
- No
Release & devices
- Release date
- 4 May 2021
- Theme
- Ancient Greece, Books, Mythology
More to play
More games from Relax Gaming
Check real-money availability
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