Sky and Friend React To | Minecraft: Fallen Kingdom Series By 

I'm glad you agree with the idea of any sequels being more prequels as the King as a character has fascinated me ever since I watched the whole series even more so once you really listen to the lyrics, Fallen Kingdom is obviously the King telling the tragic story of how his Kingdom collapsed and the new one (Rising Kingdom) is him recounting his story to his new citizens (notice the past tense of the lyrics and the first person POV in the lyrics) and saying how no matter how awful things turned out he doesn't regret it despite how much pain and trauma its inflicted on himself and others. I genuinely look up to the King as the sort of person I want to be (ignoring the creating a Kingdom and huge loss of life ofc).

Herobrine probably wanted to use the staff to control the dragon and rule all of overworld and nether. Because of king he couldn't find the end portal and got his staff stolen.