Void Chickens who eat every day mature after 3 nights have passed. A mature and fed void chicken produces a Void Egg every day, which can be placed in an Incubator to hatch another void chicken, or sold for 65g. The Void Egg can be used in cooking recipes calling for an egg.
A jet-black egg with red flecks. It's warm to the touch.
Void Chickens may be sold the same way as normal chickens. The more hearts the animal has, the higher its sell price. A new-born chick sells for 252g, and a maximum-heart Void Chicken for 1,040g, the same as for normal chickens.