Series
Nitropolis series
Nitropolis series: ELK Studios' apocalyptic formula keeps mutating
Unlike a conventional sequel chain, the Nitropolis series is ELK Studios' evolving animal-gang franchise, built on a ruined-city setting, oversized symbols and reel modifiers rather than one fixed win system. Nitropolis established the 6x4 screen, pay-both-ways action and a 10,000x ceiling; later releases repeatedly changed the mathematical pressure beneath that recognizable world.
Ranked by Slot Score
| Game | Year | RTP | Volatility | Slot Score |
|---|---|---|---|---|
 NitropolisELK Studios | 2020 | 96.1% | High volatility | 75 |
 Nitropolis 2ELK Studios | 2021 | 95% | Medium volatility | 70 |
 Nitropolis 3ELK Studios | 2022 | 95% | High volatility | 83 |
 Nitropolis 4ELK Studios | 2023 | 94% | High volatility | 76 |
 Nitropolis 5ELK Studios | 2024 | 94% | High volatility | 77 |
 Nitropolis TVLatestELK Studios | 2025 | 94% | High volatility | 72 |
The machinery shared across Nitropolis
- Setting: armed animal crews operate inside a comic-book city shaped by crime and apocalypse.
- Screen behavior: expanding reels, symbol changes and oversized symbols make the grid less stable than a conventional fixed-reel slot.
- Bonus rhythm: free spins or respins concentrate the strongest modifiers into distinct feature phases.
- Series rule: the characters and city remain familiar while ELK changes ways, volatility, multipliers and bonus access.
The first mechanical revision arrived quickly. Nitropolis 2 retained the 6x4 base and 10,000x cap but moved from high to medium volatility, increased the listed ways from 85,155,840 to 191,102,967 and added stacked, splitting, transforming and sticky-wild behavior. That made the sequel busier at symbol level without raising the payout ceiling.
Nitropolis 3 was the decisive break. It replaced the enormous ways count with a 4,096-way, pay-both-ways cascade system and lifted the maximum win to 50,000x. Nitropolis 4 and Nitropolis 5 kept that sharper framework, adding mystery symbols, random multipliers, removal effects and level progression. The fourth entry narrowed the top bet to 5, while the fifth restored a wider range and added a bonus-bet route.
Nitropolis TV changes the presentation and bonus selection more than the ceiling: its 6x4, 4,096-way setup returns to a 10,000x cap and lets the player choose among free-spin modes. It reads as a format experiment after three increasingly severe numbered sequels, not as the next ceiling increase.
Where the risk changed
- Nitropolis: huge listed ways, high volatility and the original 10,000x city blueprint.
- Nitropolis 2: medium volatility, more listed ways and denser symbol modification at the same cap.
- Nitropolis 3: cascades, 4,096 ways and a fivefold jump to 50,000x.
- Nitropolis 4 and 5: the 50,000x branch gains level-based modifiers, mystery symbols and random multipliers.
- Nitropolis TV: selectable free-spin modes replace ceiling escalation as the main distinction.