The question is, why is Aang trying to contact Korra about Yukon? Why is he important?
Yukon is Amon's father tbqh. Amon's story is half truth - Aang and Zuko were the bandits what killed his dad and his mom could have been accidentally killed in the fighting
Predix: Republic City will be lost to Amon and the revolution at the end of this season, and the second season will focus on battles for the rest of the world (hopefully letting us revisit places Aang & co. went to!)
I'm thinking Korra loses her bending at the end of S1 and S2 is her learning to fight without it. This could lead to trips to the Kiyoshi warriors, maybe another Fire Nation swordmaster, some chi blockers somewhere, maybe even Ty Lee's circus? This would also let her experience the oppression and etc the Equalists are talking about so she can better restore balance and such
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