Wishing Horse of Oz (Version 2)

The magical kingdom of Oz is happily doing all the wonderful things it does in peace and happiness, not knowing that a far off evil and grasping king with the name of Skamperoo, is planning to make all of them his subjects and slaves by the use of a magic set of emeralds. And a horse of course. A horse that he got by magic but a horse with a mind of its own. What mischief will come to the sweet inhabitants of Oz?