Series
Book of Ra series
Book of Ra series: how Greentube expanded the book-slot formula
The Book of Ra series is Greentube's Egyptian book-slot franchise, built on a book symbol that serves as wild and scatter before free spins select an expanding symbol. Book of Ra established that formula in 2005 on a 5x3 grid with nine paylines, high volatility, a gamble feature and a 5,000x maximum win.
Ranked by Slot Score
| Game | Year | RTP | Volatility | Slot Score |
|---|---|---|---|---|
 Book of RaGreentube | 2005 | 92.13% | High volatility | 52 |
 Book of Ra deluxe 10: Win WaysGreentube | 2022 | 95.15% | High volatility | 77 |
 Book of Ra Multi Card Bingo DeluxeGreentube | 2022 | 93.89% | High volatility | 50 |
 Book of Ra Deluxe Win WaysLatestGreentube | 2023 | 95.13% | Medium/High | 75 |
Book of Ra deluxe carried the name forward in 2008, but the cataloged later branches show the larger mechanical shift. Book of Ra deluxe 10: Win Ways replaces the compact fixed-line screen with a 10x4 layout, 251,957 ways, cascading wins and bonus buying. The expanding-symbol bonus remains recognizable, but the route into and through wins becomes much denser.
Book of Ra Multi Card Bingo Deluxe moves sideways rather than upward. It retains the Egyptian book code and expanding-symbol free spins, then combines them with a progressive jackpot and a bingo-oriented format. Its 1,500x ceiling is lower than the original's, so the jackpot layer, not a larger fixed maximum, supplies the added reward pressure.
Book of Ra Deluxe Win Ways compresses the multiway idea into a 6x3 grid with 117,649 ways, cascades, bonus buying and medium-high volatility. Across the series, the book-trigger identity stays fixed while the win system changes from nine paylines to large multiway grids and a bingo hybrid.