A wild stands in for other symbols to help complete a win — much like a joker. Base wilds simply substitute; the variations are where the value sits:
- Expanding wild — grows to fill a whole reel.
- Sticky wild — stays in place for one or more following spins.
- Walking wild — moves across the reels on successive respins.
- Multiplier wild — multiplies any win it completes.
Games that are really just their wild
In a few famous slots the wild is not an extra; it is the whole engine, and knowing that tells you where the game's return lives:
- Starburst (NetEnt, 2012) has no free spins at all. A wild landing on reels 2, 3 or 4 expands to fill the reel and awards a respin, up to three in a row. Everything above a base win in that game comes from stacking those expanded reels.
- Dead or Alive 2 (NetEnt, 2019) is built on sticky wilds in its free spins: each wild stays for the rest of the round, and the top prize comes only from filling all five reels with them. The base game barely matters; the round is the product.
- Book of Dead (Play'n GO, 2016) uses a wild that doubles as the scatter, and in free spins a randomly chosen ordinary symbol expands to cover its reel. That expanding symbol is not a wild — it pays only as itself — which is why a screen full of it can pay nothing when it is a low symbol.
Multipliers that stack, and ones that do not
Where several multiplier wilds take part in one win, the paytable decides whether they add (2× + 3× = 5×) or multiply (2× × 3× = 6×). Games with multiplying wilds carry higher ceilings and thinner odds of reaching them; the maximum win figure is usually built on that stacking. A "wild multiplier up to 10×" is a ceiling for one symbol, not a promise about the win.
What to check
Wilds rarely substitute for scatter symbols, so a screen of wilds does not always trigger the bonus. Read the paytable for which wild type a game uses and whether wilds appear in the base game, the free spins, or both. It is one of the clearest signals of where a game's wins are concentrated, and it feeds directly into its volatility.