Verified provider facts · 19 October 2026
Book of Cats slot guide
Book of Cats is a very-high-volatility 6×3 BGaming slot with ten lines, a special sixth reel and an expanding-symbol free-spin round.
Verified snapshot
Book of Cats facts that survived the source check
Read the trigger before the theme. The sixth reel is what separates this title from a familiar five-reel book layout. It participates in the winline expansion and also holds the cell used to select the expanding symbol for free spins. This table keeps provider statements separate from fields that were absent on the official page. “Check in game” is a deliberate result: it prevents an RTP, stake range or feature flag from a different operator build becoming a false universal claim.
| Field | Verified answer |
|---|---|
| Provider | BGaming |
| Provider API symbol | BookOfCats |
| Release | 8 July 2020 |
| Format | 6×3; 10 paylines |
| Mechanic | Sixth-reel expansion · book free spins |
| RTP | 96.99% |
| Volatility | Very high |
| Maximum | 8,202× bet |
| Bonus buy | Yes |
| Mobile | Official page states mobile optimisation |
Demo status
Mechanic preview without an unverified iframe
No provider-hosted iframe endpoint could be verified as reachable from the build location, so this page uses an original mechanic visual instead of loading an untested frame. The preview below is original editorial artwork, contains no wagering controls and does not simulate a win. Use it to identify the layout and feature family before opening the live information screen.
Play — 22BET ↗
Core mechanic
How Book of Cats builds a round
BGaming publishes a 6×3 layout, ten lines and the exact game ID BookOfCats. The Golden Book serves as both wild and scatter. In the base game it can substitute for regular symbols while also counting toward the feature trigger.
The winline-expanding feature can extend a regular line through the special sixth reel. That extra reel should not be confused with a sixth standard column using the same rules as the first five; its role is tied to the game’s expansion design.
The current provider record lists 96.99% RTP, very high volatility and an 8,202× maximum multiplier. It also supplies euro maximum-win examples, but multiplier is the portable measure because the available stake range can differ by operator.
Play — 22BET ↗Feature round
What changes in the bonus
Three or more Golden Books trigger ten free spins and select one regular symbol from the sixth cell as the expanding symbol. When that symbol forms an eligible win, it can expand across its reels. Three more books retrigger the round.
BGaming marks Buy Bonus and a gamble round as features. The gamble asks the player to guess card colour or suit after a win, while Buy Bonus jumps to free spins. They are separate optional actions and may be hidden in particular markets.
Play — 22BET ↗Concrete rule example
One round, without an invented win
Assume three Golden Books start ten free spins and the Bastet mask is selected in the sixth cell. A later spin lands masks across enough of the active reels to make a line. The chosen masks then expand on their reels under the feature rule. If the symbols do not first create the required win, their presence alone does not force an expansion payout.
Play — 22BET ↗RTP and session shape
What the numbers mean in a short session
A 96.99% RTP is a theoretical average across a very large number of rounds, not a target for ten free spins. Very high volatility means the path around that average can be uneven. Confirm that the loaded game still shows BookOfCats and the same RTP before applying these reference facts.
Availability check: Not asserted: the public BoyleSports lobby could not be verified from the research location.
Mechanic neighbours
Related slot guides
Search questions
Book of Cats FAQ
Is Book of Cats the Megaways version?
No. This page covers the original game with ID BookOfCats, a 6×3 and ten-line setup.
How many free spins are awarded?
Three or more books award ten free spins.
What becomes the expanding symbol?
A regular symbol is selected through the sixth cell when the feature starts.
What RTP does BGaming publish?
The current official record lists 96.99%.
Can the bonus be bought?
BGaming lists Buy Bonus, but operator and market availability can differ.
Primary evidence
Provider sources
- bgaming.com/games/book-of-cats
- bgaming.com/wp-content/uploads/2025/04/63e9eaffef764d2e8ed0b19c_bookofcats.pdf
The source list supports game facts only. It does not establish current BoyleSports lobby availability.
Final live check
Search Book of Cats, then verify the version
Use the exact title and provider, open the help panel and stop if the RTP or feature set differs from this checked record. Set the session amount before the first round; no mechanic changes the independence of the next result.
Play — 22BET ↗
