Feathers are inventory items in KQ6 and KQ7.
Background[]
The Feather in KQ6, is a black Horse feather. It is an unusually large coal-black feather that Alexander found on the Isle of the Sacred Mountain. It was possible that this feather came from the wings of Night Mare when she came to feed off of noxious flora. Alexander used it for the Magic Paint which required '1 Black Horse Feather'. He used it in the spell by stirring the contents of the teacup. After the black hue drained into the mixture, Alexander discarded the drained feather.
Valanice found a chicken feather on the Rubber Chicken.
Feathers of many types appear in the King's Quest Games, including Eagle Feather and Chicken Feather in KQ3.