As for who Amon is, I'm thinking it's a manifestation of past Avatars trying to protect the world from having a future tyrant like Fire Lord Ozai. That would explain why Korra has been unable to communicate spiritually with past Avatars except for like a few Aang flashbacks.
Ehhhh that sounds terrible. Aang only talked to Roku for a very long time, and IIRC he only rarely talked to Kiyoshi. The water and previous air Avatars had like 1 sentence each in the finale only.
And the better explanation is that Korra sucks hard at the spiritual stuff. That's why she can't even talk to Aang, just see flashbacks.
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foolmo
at work