Promo first made available via Santa's Renegades.
Setup: Add the Wild Die to the bag with the other dice.
Gameplay: If the Wild Die is rolled, it is chosen by a player just like any other die. If the # symbol is showing, the die can be placed on any space showing a number. If the color symbol is showing, the die can be placed on any space showing a color. If a space needs both a specific number AND color, the Wild Die cannot be placed there.
For more information, visit the BGG listing.