Cascading reels, also known as avalanche reels, are a feature commonly found in slot games where winning symbols disappear after they form a winning combination, allowing new symbols to "cascade" down and fill the empty spaces. This can create additional opportunities for winning combinations in a single spin. Each time symbols are removed, the reels "cascade," and new ones fall into place, potentially triggering more wins. This process can continue until no more winning combinations are formed. Cascading reels increase the excitement of the game by offering multiple chances to win from one spin.