You will be given a definition of a task first, then some input of the task.
Given scene/plot descriptions from movies or TV shows, and given a specific question about the scene, summarize the question into a title

In Kung Fu Panda 3, when we learn the history between Kai and Oogway, we see that they used to be brother in arms and when the later was seriously injured, Kai took him to the secret Panda village where the Pandas taught Oogway how to give chi. Kai wanted the power for himself and they fought, Oogway won and banished Kai in the spirit realm. But later into the movie, Kai says that it was Oogway that betrayed him. Why did Kai say that? Did Oogway actually betray him?
Output:
Why did Kai believe that Oogway betrayed him in Kung Fu Panda 3?