Herzog Ernst
Young Duke Ernest wants to become a good knight. The circumstances are not in his favor: The emperor wants to claim the Duke´s castle and marry his mother. He has Ermest wrongfully accused of murder and thrown in the dungeon. Duke Ernest´s only chance to escape a death sentence is to join the army and to go to the orient in search of the legendary Carbuncle Stone. He´ll have to overcome carnivorous rocks, magnetic mountains, the giant bird Rock and many more.
Starring Wolf-Dietrich Sprenger
Watch "Herzog Ernst" on Kanopy released in 1993. It's a fantasy and animation movie, and has a rating of 7 out of 10 from Imdb which is usually fine for this kind of movie.