Cascading reels and cluster pays

Cascading reels

Cascading reels go by several names, including tumble, avalanche and chain reaction. The idea is the same in each case. After a spin, any symbols that form a win are removed from the grid.

The symbols above them then drop down to fill the gaps, and new symbols fall in from the top. If the new layout forms another win, that is removed as well, and the process repeats until no more wins appear.

All of these new symbols are chosen by the random number generator when the cascade happens, as described in how online slots work. You pay for the first spin only, and each extra step in the chain is part of that same paid spin.

Cluster pays

A cluster pays slot has no paylines and does not use the left-to-right rule of ways slots. Instead, a win forms when a minimum number of identical symbols touch each other, usually horizontally or vertically. The minimum is often 5, though games vary.

The bigger the cluster, the higher the payout. Grids are often square, such as 6 by 6 or 7 by 7, and diagonal contact normally does not count. The paytable lists the cluster sizes and what each one pays.

Why they are often combined

Cluster wins fit naturally with cascades because a cluster can be cleared and a new one can form in the same place. A single spin can produce a chain of wins, which makes the game feel lively and gives designers room to add extra rules.

Cascades also work with other layouts, including Megaways grids, where the number of ways is recalculated after each drop. Do not treat the two terms as meaning the same thing, though. A game can have cascades without clusters, or clusters without cascades.

Multipliers that grow during a cascade

Many cascade games add a multiplier that rises with each step in the chain. For instance, the first win may pay at 1x, the second at 2x, the third at 3x and so on. In free spins the multiplier sometimes carries over from spin to spin instead of resetting.

Here is a simple example with invented numbers. A chain has three wins of 2 EUR, 3 EUR and 4 EUR. With a multiplier that rises 1x, 2x, 3x, the total is 2 × 1 + 3 × 2 + 4 × 3 = 2 + 6 + 12 = 20 EUR. Without the multiplier, the same chain would pay 9 EUR.

Multipliers raise the size of the wins, but the game's design offsets this elsewhere. Long chains are rare, and the base game normally returns less often to pay for them, which is why these games frequently carry higher volatility. The chance of each chain is already built into the game's RTP.

What these mechanics do not change

A cascade can make a spin feel like a streak, yet each step is generated independently and the game does not make a longer chain more likely because the previous one was short. There is also no sign in the grid that tells you a big chain is coming.

The house edge is determined by the game's overall RTP, not by its mechanics. A cluster game with cascades and a game with plain paylines can both have the same long-run return.

Because a single paid spin can contain many steps, the animation can run for a while and the screen can show several wins in a row. Look at the balance after the spin ends to see the true result, since small wins inside a chain can still add up to less than the bet.

Playing notes

Check the paytable for the minimum cluster size, the multiplier rules and whether the multiplier resets. These details differ between games and affect how a round plays out.

Set a budget before you start and keep to it. Fast, animated play can hide how much you have spent, so use the session timer or limits your casino provides. Further help is on our responsible gambling page.