Ronno--> I'm not so sure about Dumbledore's death, I didn't really like J.K. Rowling for doing that but still, we do not quite know yet if it was unessesary, because it was at the end of the book. I mean, she probably was planning this from the beginning. 1) to add excitement, and 2) to show that Snape was a traitor... besides Dumbledore was getting quite old.. He probably needed to die... maybe not like that but he needed to die... she also may have wanted to make you hate Snape (which worked quite well for me

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((sorry if this ruins it even more for others))