The Megaways mechanic is an innovative feature in slot games that provides a variable number of winning combinations on each spin instead of fixed paylines. Created by Big Time Gaming, this system allows the reels to change in height, leading to different symbols appearing, which can result in hundreds to thousands of ways to win. The mechanic often incorporates cascading wins, where successful symbols are replaced by new ones, enabling multiple wins from a single spin. This unpredictability and variety enhance the excitement of gameplay, making each turn unique.