The wild symbol replaces all symbols. This game is not scattered because it triggers a free spin by unlocking 9 symbol blocks in the middle of the game grid.
This slot does not have a spinning reel. Instead, the symbols fall on a 7x7 grid in a cascade. Cancel the winning combination and the new symbol is in place. This situation continued until there was no new victory after the fresh decline. Unlocking the center portion of the nine symbols in a sequence will trigger a free spin.