Series
Mr. series
The Mr. series changes engines without abandoning classic slot symbols
The Mr. series is Endorphina's retro-symbol franchise, built on familiar bells-and-fruit imagery and a carryover gamble feature rather than one fixed reel engine. Mr. Jingle Bells established the line in 2024 as a 3x3 Christmas slot with five paylines, a multiplier and a pick-object bonus. Its small grid and 0.01 minimum bet place the emphasis on short, readable outcomes.
Ranked by Slot Score
| Game | Year | RTP | Volatility | Slot Score |
|---|---|---|---|---|
 Mr. Jingle BellsEndorphina | 2024 | 96.01% | — | 59 |
 Mr. Bells 40LatestEndorphina | 2025 | 96.06% | High volatility | 72 |
Mr. Bells 40 rebuilt that format in 2025 around a 5x4 grid, 40 paylines and high volatility. Fruit replaces the Christmas setting, while hold-and-win respins, bonus symbols and fixed jackpots displace the original pick game and multiplier focus. The gamble option survives, but almost everything around it shifts toward longer bonus buildup and a denser screen.