Cascading reels, also known as tumbling reels, refer to a slot feature where winning symbols explode and disappear, causing symbols above to cascade down into empty spaces. This creates the potential for additional wins from a single spin on such popular platforms as Lukki. The cascading process continues until no more winner combinations emerge.
Table of Contents
How Do They Work?
Rise of Megaways Slots
Math Behind Cascading Reels
Future Evolution of Tumbling Reels
How Do They Work?
The cascading reels functionality relies on programming that evaluates symbol combinations not just from left to right, but also from right to left and sometimes diagonally. Unlike a traditional slot where a spin ends after calculating standard pay, a cascading slot allows the spin to continue after removing winning combos. Here’s a quick breakdown:
- The reels spin and land on a combination of random symbols.
- The game checks for winning symbol clusters and highlights them.
- Winning symbols explode and disappear, while symbols above fall down to fill the gaps.
- The slot checks new symbol arrangements for additional wins.
- Steps 3 and 4 repeat until no more cascades occur.
Origins of Tumbling Reels
The cascading reels system traces its origins to the early 1990s, when an Australian slot maker called Ainsworth Game Technology first introduced it in a slot called Racing 7s. The concept later appeared in popular land-based slots like Money Storm. But cascading reels only truly soared in popularity with the rapid growth of online slots in the 2000s.
Internet and mobile slots offered game designers the flexibility to experiment with innovative features like tumbling reels more easily than physical slot machines. Leading software studios like NetEnt, Playtech, Microgaming, and IGT have all incorporated cascading reels into many of their top-performing game titles. As the trend caught on, almost every slot developer now integrates some form of cascading or avalanching reels into their games.
Rise of Megaways Slots
No conversation about cascading reels is complete without mentioning Australian studio Big Time Gaming. Although not the pioneer of tumbling reels, Big Time Gaming weaponized the feature in 2016 through its now iconic Megaways game mechanic. The Megaways engine utilizes an expanding reels system that randomly generates hundreds of thousands of paylines combinations. Combined with tumbling reels and unlimited win multipliers, Megaways slots created a new genre that has dominated the industry for years.
Math Behind Cascading Reels
Slot designers don’t adopt features randomly. There is thoughtful math driving the integration of game mechanics like cascading reels. Tumbling reels increase hit frequency and payout percentage by enabling multiple wins from a single bet. This benefits players through more gameplay excitement and rewards. Operators also win through faster turnover of slots and reduced volatility.
Here is a comparison of key mathematical averages in slots with and without cascading reels.
| Metric | Standard Slot | Cascading Slot |
| Hit Frequency | 25% | 45% |
| RTP (Return to Player) | 96% | 97% |
| Max. Win | 10,000x | 50,000x |
| Volatility | High | Medium |
As demonstrated above, the averages clearly tilt in favor of slots with cascading reels. The hit frequency practically doubles from 1-in-4 spins to almost 1-in-2 spins paying a win. Similarly, the long-term RTP increases by 1% while the maximum possible win multiplies five-fold. Even volatility reduces, making payouts more consistent.
Future Evolution of Tumbling Reels
Slot developers continually tweak tumbling reel mechanics to create fresh gameplay. Some titles already feature multiple cascading stages within a single spin for bigger chain reactions. Other innovations include reactive wins where new symbols emerge after each cascade or expanding reels that grow with each avalanche. Slot makers even combine cascading reels with cluster pays, symbol transformations, and a host of other features for truly dynamic gameplay.
As slots embrace cinematic graphics and console-style gaming through HTML5 technology, we can expect more layers added to cascading reels. Perhaps 3D cascades, particle effects on winning combos, or synergies with bonus games.