A Stacked Wild is a wild that covers more than one section of a reel – 3 or 4 blocks generally make up a stacked wild. Crystal Waters and Ronin are two examples of stacked slot machines. Other slots with stacked wilds are Wolf Run and Treasure of Troy. Stacked wilds are a feature of both normal gameplay and are included in some free spins bonus rounds. In Treasure of Troy the gameplay is slightly unique in that every symbol is a reel and so the stacked principle applies to every symbol not just the wilds.
Battleship and the Dungeon & Dragons slot also include stacked wilds. The Hulk slot has an expanding wild on the center reel while games like Sparta slot have stacked wilds on reels 2, 3 and 4. Cherry Luck slot follows the same fashion for scatter positions.