Aitvaras is a household spirit in Lithuanian mythology. Other names are Kaukas, Pūkis, Damavykas, Sparyžius, Koklikas, Gausinėlis, Žaltvikšas, and Spirukas. Aitvaras is identical to the Latvian Pūkis. An Aitvaras looks like a white or black rooster with a fiery tail (meteorite). An Aitvaras may hatch from an egg of a 9–15 year old rooster. If the Aitvaras dies, he becomes a spark.
In many cases, this Lithuanian creature is described as having the appearance of a rooster while indoors and the appearance of a dragon outdoors. An Aitvaras will lodge itself in a house and will most often refuse to leave. It brings both good and bad luck to the inhabitants of the house. Aitvaras provide their adopted home with stolen gold and grain, often getting the household into trouble. According to many, an Aitvaras can be purchased from the devil - the price being that person's soul.