Gribblefritz is a planet that is located at a distance of a few zillion miles from Earth.
Gribblefritz is most likely a planet housing one or more civilization. It is known to the population of Zipton, who consider it a potential second home.
In a questionable retelling of the Darkwing Duck mythology, Darkwing and Negaduck escape their doomed planet, Zipton, in rockets set for Gribblefritz. They never reach the planet because they bump into each other, sending them in different directions.