Series
Diamond Mystery series
Diamond Mystery series: Greentube's changing classic-slot chassis
Unlike a sequel line that keeps raising one headline maximum, Greentube's Diamond Mystery series rebuilds a classic fruit-and-gem formula through different line counts, reel heights, jackpot layers and mystery-symbol systems. The Diamond Mystery slots retain familiar crowns, stars, 7s and fruit while changing how densely the screen pays and how much feature machinery sits behind it.
Ranked by Slot Score
| Game | Year | RTP | Volatility | Slot Score |
|---|---|---|---|---|
 Diamond Mystery 40 Imperial CrownGreentube | 2023 | 95.48% | Medium volatility | 50 |
| 2023 | 95.48% | — | 50 | |
| 2023 | 95.48% | Medium volatility | 53 | |
| 2023 | 95.48% | — | 51 | |
 Diamond Mystery Fruitilicious deluxeGreentube | 2024 | 95.48% | Low/Medium | 53 |
| 2024 | — | 40 | ||
 Diamond Mystery Stars InfernoGreentube | 2024 | 94.25% | Medium volatility | 57 |
 Diamond Mystery 100 Wild FireGreentube | 2024 | 95.48% | — | 55 |
 Diamond Mystery Fortune StreaksGreentube | 2024 | 95.48% | — | 59 |
 Diamond Mystery - 40 Charming 7'sGreentube | 2024 | 95.48% | — | 49 |
| 2025 | 95.48% | Medium volatility | 56 | |
 Diamond Mystery - 100 Charming 7'sLatestGreentube | 2025 | 95.48% | — | 49 |
| — | — | 31 |
- Greentube · 2025RTP95.48%Score56Medium volatility
Diamond Mystery 40 Imperial Crown established the cataloged foundation in 2023 with a 5x3 screen, 40 paylines, wilds, scatters and medium volatility. The Imperial Crown Deluxe lane then became a controlled payline experiment: 10 lines with expanding symbols and a progressive jackpot, 20 lines with fixed jackpots and mystery symbols, and a 5x4 version with 100 paylines.
The Imperial Crown chassis
- Fixed-line wins: the main branch uses defined payline counts rather than a cascading or cluster system.
- Wild and scatter support: these symbols remain the basic win and trigger tools across the Imperial Crown and Charming 7's lanes.
- Symbol expansion: several Deluxe and Wild Fire variants enlarge symbols to increase coverage on the fixed grid.
- Post-win gamble: a Risk/Gamble double game recurs across the Deluxe, Wild Fire and Charming 7's releases.
- Jackpot overlays: progressive or fixed jackpots add a separate reward layer to many branches.
Diamond Mystery Fruitilicious deluxe compressed the idea to 5 paylines and a low-to-medium profile, but added a bonus game, fixed jackpots and a 5,000x maximum. At the other extreme, the 100-line Imperial Crown and Wild Fire releases use 5x4 screens to create denser fixed-line coverage rather than a taller cascade system.
The sharpest feature shift came with Diamond Mystery Stars Inferno in 2024. Free spins, respins, multipliers and a prize wheel moved the franchise beyond its restrained wild-scatter base. Fortune Streaks followed with extra free spins and a pick-object bonus, while Diamond Mystery - Fruitful Frenzy - Cash Accumulator combined mystery symbols, free spins and a pick bonus on 10 paylines.
How the Diamond Mystery branches differ
- Imperial Crown: the foundation scales the same classic frame through 10, 20, 40 and 100-line editions.
- Fruitilicious: the format contracts to 5 lines and a lower-volatility profile while retaining bonus and jackpot layers.
- Inferno and Fortune: free spins, respins, multipliers, wheels and pick bonuses replace pure line-count variation with feature depth.
- Charming 7's: 40 and 100-line versions emphasize mystery symbols, followed by a 6-reel format change.
- Cash Accumulator: the franchise folds collection-style bonus logic into its classic fruit framework.
Diamond Mystery is therefore less a linear escalation than a kit of interoperable classic-slot parts. Line count controls hit coverage, reel height controls symbol space, and jackpots or mystery symbols determine how far each edition departs from the plain fruit-machine base.