Book 3: from the very beginning, Ty Lee is a part of the Gaang, Zuko's firebending is rapidly growing to equal his sister's and Azula herself is already starting to hallucinate
. Sokka is now Ty Lee's boyfriend, while Aang and Katara are closer then they ever were even at the end of the series, and everybody out to get them all seem a lot more lethal than they used to be. As well, Ty Lee turned out to have been an airbender, and airbending unconsciously since Book 2.
During the story's equivalent to Boiling Rock, Mai pulls a Heel Face Turn
, leaving Azula
alone and on the fast track to insanity. Sokka seems to be powerleveling
in the last few episodes, Aang actually has a plausible reason for almost getting Ozai'd, and everything gets turned up to eleven
. And then, just when it all seems sorted, the sequel hook hits. Contains frequent Word Of God
and clarifications of the world, such as the nature of shamans and the differences between benders being between power and skill. Still, while some characters (ie, Sokka, Ty Lee) ring true, others seem to fall comparatively flat. And there's a big YMMV glut in the epilogue. Like Sokka dicovering, to his great dismay, that he's a waterbender.