Series
Sparky and Shortz series
Sparky and Shortz slots: one duo, two reel engines
The Sparky and Shortz series is Play'n Go's monster-led science-fiction franchise, built on free-spin bonuses, stacked symbols, and multipliers while allowing the reel engine to change around its title characters. Sparky and Shortz set the formula in 2021 on a 5x3 grid with 10 paylines, high volatility, random multipliers, and a 10,000x maximum.
Ranked by Slot Score
| Game | Year | RTP | Volatility | Slot Score |
|---|---|---|---|---|
 Sparky and ShortzPlay'n Go | 2021 | 94.24% | High volatility | 62 |
 Sparky and Shortz Hidden JoulesLatestPlay'n Go | 2023 | 96.2% | Medium volatility | 77 |
Sparky and Shortz Hidden Joules rebuilt that format in 2023 as a 7x7 cluster-pays game with cascades, mystery symbols, colossal symbols, symbol removal, and extra wilds. It also moved to medium volatility and reduced the maximum to 6,000x, while its listed RTP rose from 94.24% to 96.2%. The original is the sharper fixed-line option with the higher ceiling; Hidden Joules trades some peak reward for a busier sequence of cluster reactions and grid changes.