What the Legend of Korra had lacked up to this point was an interesting villain. Amon and Unalaq had superficially seemed different but underneath were rather similar: both water benders shaped by sibling rivalry and with hidden motives. Zaheer is quite different.
A sort of anarchist and a genuine revolutionary, Zaheer is not a person in conflict with himself. His agenda is revealed through the series but it is not a secret from his followers. Of all the characters in both The Legend of Korra and Avatar, he is surprisingly at ease with himself and this is matched with his powers. He eventually gains the self-discipline to be able to fly unaided using air-bending and he’s also portrayed as being at peace with the spirit world.
It’s an interesting choice but a clever one. Zaheer’s lack of inner turmoil is an unusual one for a pop-culture version of a fanatic. Henry Rollins gives the character an intimidating intensity which elevates the contracts with Korra. Her character has been one at odds with herself throughout and lacking a sense of purpose and direction.
Ba Sing Se remains a weak point. The worldbuilding has never been shy about its Japanese and Chinese influences but Ba Sing Se has always been rather too obviously a stand-in for Beijing. The parallels are intensified by making the Earth Queen resemble a stereotype of a despot and modelled on the late nineteenth century, Empress Dowager Cixi.
A more interesting city is Zafou: a technology-led model city that has solar-punk elements as well as hints of art-deco. Zafou his a clear indication of a world that has its own direction to follow rather than simply borrowing from history.
Books 1 and 2 both ended with resolved stories. They had open endings that promised new possibilities but Korra in particular ended in a better place emotionally and as a character then where she started. Book 3 changes that. The plot around Zaheer is complete but as a story arc, Korra’s plotline is overtly incomplete. There is a momentum for Book 4 that the previous seasons lacked.