Tumble & Cascading Reels Slots
Tumble and cascading reels remove winning symbols and drop new ones into the gaps, so a single paid spin can settle several waves of wins.
How tumbles and cascades work
A tumble, also called a cascade or an avalanche, removes the symbols that formed a win and drops new symbols into the empty cells. The new arrangement is then evaluated again, and the chain continues until a drop produces no win. Every step belongs to the same paid spin, so a player stakes once and can settle several waves of wins.
A tumble is not a respin. In a Respins feature the reels spin again as a distinct event, whilst a tumble only refills the cells the win vacated. The difference shows up in the rules, because retrigger limits and feature counters usually treat the whole tumble chain as one spin.
The mechanic appears with several win systems. Pay Anywhere games use tumbles to clear counted symbols, and Cluster Pays games use them to break up and rebuild connected groups. Payline games can tumble as well, although the pairing is less common.
Many tumble games attach a progression to the chain. Some designs raise a win multiplier with each successive tumble, and others hold Multipliers on the grid that apply when the chain ends. The rules should state whether the progression resets between spins and whether a bonus round changes the behaviour.
Three disclosures describe a tumble game properly. The rules should state what triggers a tumble, whether any symbols persist through the chain, and how multipliers interact with the sequence. A game that documents all three can be judged on its published numbers rather than on guesswork.