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Online slot games featuring expanding wild symbols.
What exactly are Expanding Wilds?
Expanding wild symbols are a special feature of the placeholder symbol. The Wild single symbol expands either vertically or horizontally. In most cases, the Wild expands to the full height of a reel, but it can also spread sideways to the adjacent fields. The exact way the expansion occurs depends on the slot machine. This function can be available in the base game or used as an extra feature in a free spin round or bonus game.
This is how expanding wilds work.
Basic information about the wild expansion
When a Wild symbol with an expanding feature lands during regular gameplay, it will expand according to the game rules. This expansion can occur either in a circular or diagonal manner across the reel. The crucial aspect is that, ideally, it not only completes or enhances symbol rows but also generates wins across multiple paylines simultaneously.
Is there a correlation between vertical expansion and wild reels?
An almost classic version of the Expanding Wild is the vertical expansion. In this case, the individual Wild symbol expands to cover the entire reel it landed on. However, you should not confuse this with a Wild Reel, which is a whole reel acting as a placeholder. With the Expanding Wild, only the currently visible symbol positions are turned into Wilds when a Wild symbol lands on that reel. Furthermore, this usually happens after the spin, when all the reels have already come to a stop.
Horizontal and diagonal spread.
Unlike vertical expansion, horizontal or diagonal expansion of the wild symbol usually does not extend the entire length of the reel field. A horizontal expanding wild often occurs in conjunction with a vertical expansion. This means that it spreads to surrounding symbol fields around the original placeholder symbol. Depending on the online slot, the number of fields occupied by the expansion can vary. For example, it can expand to 8 additional fields surrounding the individual wild symbol, as seen in the Explodiac Slot by Bally Wulff.
Enhancing Wilds with added features.
It's not uncommon for expanding wilds to make an appearance alongside other features. For instance, this enhancement can also come into play in conjunction with 2-Way Pay, respins, or symbol upgrades, as seen in popular games like NetEnt's Starburst or Merkur's slot machine hit Eye of Horus during the free spin round.
