Series
Book of Santa series
The Book of Santa series began in 2019, when Endorphina fixed Christmas imagery to a 5x3, 10-payline book-slot formula built around free spins and expanding symbols. Book of Santa established the line with a scatter trigger, a wild, expanding symbols and a double-or-nothing gamble feature. Its structure is conventional for a book slot, but the Santa, star and festival imagery gives that familiar engine a seasonal role.
Ranked by Slot Score
| Game | Year | RTP | Volatility | Slot Score |
|---|---|---|---|---|
 Book of SantaEndorphina | 2019 | 96% | — | 62 |
 Book of Santa DiceLatestEndorphina | 2024 | 96.05% | — | 68 |
Book of Santa Dice expanded the formula in 2024 without changing the 5x3 grid or 10 paylines. It retained expanding-symbol free spins and the gamble option, then added a bonus buy and random additional wilds. The original depends on landing the natural bonus trigger, while Dice offers faster access and more wild activity inside a brighter ice-and-candy Christmas setting.