So I was surfing the net and came across this website. The site (here it is: http://www.tv.com/shows/avatar-the-last-airbender/forums/what-i-think-ursa-did-theory-dobs-spoiler-13281-876239/ ) has this theory concerning Ursa's ties with Azulon's death, Ozai's rise to the throne. It's quite old because it was dated way back November 13, 2007. We've all heard those theories but, I don't know, I just wanted to share what I read in here because the theory sounds so right which implied Ursa was somewhat a killer. NOTE: This is not mine. I just read it from the website.
"I'm sure you all remember that Ozai said Ursa did treasonous things to get Ozai into power, though he never went into details. There were two main obstacles keeping Ozai from the throne that Ursa would have to rectify. First, Azulon was still alive, and naturally, no new Fire Lord could be crowned until he died. Second, Iroh was the first born, not Ozai, and therefore, even if Azulon died, Iroh would inherit the throne. First, she needed to deal with Azulon. We all know he died soon after he ordered Ozai to kill Zuko. I know many people have spoken on the possibily that Ursa assassinated Azulon, but there was no hard evidence; that is, until now. It is now known that Ursa committed treason, andit's safeto say murdering the Fire Lord is treason. No cause of death for Azulon was ever revealed, so it is likely that Ursa killed him. The pieces just fit together. Now on to the new part of the theory.Soon after Azulon died, Ozai was crowned Fire Lord, which means that Iroh was dealt with around the same time. It seems as though Iroh and Ursa had a good relationship; likely because Iroh wanted to be on good terms with what at the time was thought to be the final working (by this I mean involved in world affairs) avatar's descendant. Remember that Aang had not awoken yet, so I'm sure many assumed the Avatar was gone forever. Anyway, Ursa would not have wanted to kill Iroh unless she needed to, but she had another option. Unlike with Azulon, Ursa could kill a different person to get what she desired from Iroh. Around the time this was all happening, Lu Ten died. Curious, isn't it? Ursa knew that Lu Ten was Iroh's only family, and getting rid of Lu Ten would destroy Iroh. Since Azulon's last wish was to crown Ozai, Ursa must've told Azulon that Iroh's son had died and that he was emotionally distraught right before she killed him. Basically, Azulon had no choice. He had too much pride (as any imperial leader would) to hand the throne to someone who was unstable. It is simple to say that she would not kill her nephew, but she had to kill one of three people: her brother-in-law (Iroh), her nephew (Lu Ten), or her son (Zuko). In the case of Zuko, it would be an indirect killing, seeing as Ozai would do the actual killing. Her best option was to kill Lu Ten, and that's just what she did. Commit treasonous act #2. This may seem at first far fetched, but if you ponder it carefully, all the pieces fall into place. I will be super p!ssed if someone says TL;DR. It's not really that long,but if itistoo long for you, don't post at all."
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