First bit is a nearly impossible to read overview of "Book 2: Spirits" that popped up online:
The text apparently says:
“Having finally mastered all the elements (air, water, fire and earth), Korra has become a fully realized Avatar with all the power that the role entails. But even the strongest of Avatars can fail and Korra discovers she has much to learn when she steps into the realm of Spirits – a mysterious world that is both beautiful and dangerous. In the Spirit World, Korra soon learns that the Light cannot exist without the Dark, and in the cycle of creation and destruction, only she can restore balance to the world.”
So pretty much what we were guessing once the title of the season was announced way back.
In more substantive developments though, it the first two episodes of the season will take us back 10,000 years to look at the life of Wan, the very first Avatar of the cycle, who will be voiced by Rick Yuen of The Walking Dead:
Finally, a question and discussion primer: I read ATLA: The Search, Part 2 yesterday and really enjoyed it. They threw a lot of revelations and puzzle pieces about Zuko and Azula's past in this installment. How do you guys figure it will all tie in together in the last part?
My favorite theory is that the Face Mother changed Ikem and Ursa's faces and memories at separate times so they could start over as new people, but somehow ended up finding each other again and falling back in love without realizing it.
Also what do you think Azula's "beautiful destiny" could be, if she actually has one?