<p>For a 3rd series to work, our Avatar has to make mistakes-so they have to fall from a higher place then ever before.
Let's start our story about 80 years after Korra's ending. Our protagonist is a Fire Nation guy, who is the Avatar but does not know it. I'm thinking the Earth one after Korra was killed as a baby or toddler, and that that's only a rumour.
</p><p>Our protagonist has a personality not unlike Katniss Everdeen's:No stable background like Roku, Aang or Korra. Grows up an orphan, with a craving for knowledge. Is sort of....resigned to his fate when he discovers he is the
Avatar. Like, if he's going to do this, he might as well get started right?
His arc would revolve around empathy, something he has never really gotten, but now desperately needs to, and the personal need vs distraction value of friends or a Team Avatar.
Possible villains; a returning Red Lotus, and perhaps-I think this could be very interesting-a group who want to carry out Raava's ideals without the Avatar. Like, they think that the Avatar's existence brings suffering and imbalance, like with Roku and Sozins friendship, Aang and the Air Nomads and the Earth Avatar's grieving family-but the important thing is they want to bring balance, as we see it-just by themselves, not with the Avatar. I will call them the Silver Lotus.
Did any of that make sense? As for technology, I think have most of the world-with the exception of the Air Temples and Norther WT-be around Korra's Republic City level.
If-iiiiiiifffff-they regain the connection to the past Avatars,(this would not be easy) I think;
Quite close to Roku and Korra, sees them as wise and good role models.
Likes Aang, but also thinks he is a bit too much of an optimist.
Doesn't get on at all with the Earth Avatar before him, who is incredibly resentful she has to guide him after her life was stolen.
This guy would also use lava ending a lot, because it's awesome, and lightning. In fact he would try to learn everything, believing he needs to for duty. Again, theme of friendship comes in here.
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