 Several secondary characters have also achieved star status in certain publications, such as Grandma Duck, Donald Duck's grandmother; Gladstone Gander, Donald Duck's incredibly lucky cousin; Gyro Gearloose, an inventor who is often patronized by Scrooge; and Ludwig Von Drake, a knowledgeable professor.Scrooge also has several enemies, such as the Beagle Boys, a gang of robbers and escaped prisoners; Magica De Spell, an Italian sorceress; and South African Flintheart Glomgold and English-American John D. Rockerduck, both rival business men of Scrooge.Some characters have appeared alongside Donald primarily in animation, such as chipmunks Chip 'n' Dale ("Chip an' Dale", "Toy Tinkers") and Humphrey the Bear ("Rugged Bear", "Grin and Bear It"), as well Mickey Mouse ("The Dognapper", "Magician Mickey") Goofy ("Polar Trappers", "Frank Duck Brings 'Em Back Alive"), and Pluto ("Donald and Pluto", "Window Cleaners"), who are more often associated with the Mickey Mouse universe.