Before we look at Season 2, I want to take some time to put forth a theory that I've been laying the groundwork for thoughout this blog. If you don't care, then feel free to skip this. Also, there may be some mild spoilers for Season 2, but I'll keep them to the bare minimum.
My theory is this: Avatar: The Last Airbender, as a show, did not proceed as it was initially conceived. That's not to say that the ending and basic structure wasn't planned out ahead of time. But what I'm saying is that the writers introduced significant changes in the series mid-stream. Season 2 did not proceed as the writers originally intended, and this affected even part of Season 1.
And here is my evidence.
There was a mid-season break between episodes 13 and 14. Namely, between The Blue Spirit and The Fortuneteller. If you compare the episodes before and after, you will find that many things changed around this break, separating the season into early first season and late first season.
Hybrid animal names, for example. The Fortuneteller is the first episode where hybrid animals are consistently named by their hybrid names. They will be used consistently from that point forward.
Sokka is another example. The Fortuneteller really is the last point in the entire series where the universe seems to have a personal mad-on for Sokka. Oh, he'll be the victim of Tempting Fate here and there, but it will never be as persistent and prolonged as it was before this.
The role of Katara's necklace is yet another example. It was established in early first season as being passed down from her mother. But late first season now says that it is a Northern Water Tribe betrothal necklace, something that a person fleeing from NWT persecution wouldn't want to keep. This was something they had to do for The Waterbending Master, in order for Pakku to accept her as a student. But if they had intended that from the beginning, if it was all planned out, they could have done it much more smoothly a different way.
The depiction of the Spirit World is another example. In The Spirit World, it is clearly simply the regular world where spirits are able to appear. In The Siege of the North, it is explicitly a different place. Now, in the later episode, it is hinted that this is really the first time Aang was in the Spirit World proper, that before, it was just Aang being a disembodied spirit. But that smells of retcon.
Zhao suddenly got a character; did you notice that? In The Siege of the North, he wants a legacy for himself. In The Deserter, we find out that Zhao is all about power, without finesse or control. These are things we didn't know about Zhao before the mid-season break. Indeed, we knew nothing about Zhao before then; he was a completely blank slate villain. He had neither style nor substance.
Appa stops being a Deus Ex Machina device. The last time he rescues the Gaang from imminent death at the end of a season 1 episode is in The Waterbending Scroll. Indeed, we'll only see it again in two episodes. The last one, episode 37 (17 in season 2), is in a Big Damn Heroes moment, after he's been missing for some time. And that will be the last time he is used that way.
But there are even more radical changes between seasons 1 and 2.
The very title of the season 2 opener is such a thing. From the title onward, they give a name to that glowy thing that Aang does when he gets all badass: The Avatar State. They even talk about it as though they've always called it that; nobody ever explains where the name comes from.
The depiction of earthbending has some changes, somewhat subtle but important. They introduce this foot-plant thing that earthbenders do before they start moving earth. Indeed, we'll be getting a lot of earthbender foot fetishism from here on in. It isn't exactly a plot-point, but it is important for discussing theories of earthbending. And it's something that no earthbenders did before.
Iroh also goes through a sudden change, though not in the first episode. While Iroh had never been as enthusiastic about the whole "capture the Avatar" plan as Zuko, in season 2 he starts actively discouraging Zuko from continuing in his quest. Why? It's not really clear. There is a partial explanation, but it doesn't entirely cover why he's so adamant about it.
Even more, in the season 2 finale, Iroh suddenly starts calling what they've been doing wrong. That helping the Avatar defeat the Fire Nation has become "good." This is a rather sharp turn for someone to take, particularly in light of how he behaved in first season. There, his only problem with Zuko's quest was how obsessed he was with it. Not the quest itself, just the single-minded pursuit of it.
Zuko has a few changes too. Namely, the nature of his quest. In season 1, it was very clearly all about recapturing his honor and being able to return to his home. In season 2, this quickly shifts to him wanting his father's love and respect, something that was never mentioned in season 1.
So, what is my point in bringing all of this up? My point is that quite a few of these changes are corrections. They weren't simply changing things; they were fixing problems in the story and/or adding depth where needed. And that's where we get to the villains.
Nothing changed more radically than the depiction of the villains in season 2. There can be absolutely no question of that; its like a whole different show.
Zuko started the series quite strong. He was threatening, and he had a nice bit of theme music when he was being strong (thought that theme is shared with the entire Fire Nation). He even got to beat Zhao in an Agni Kai, to prove that he was a skilled firebender, despite obviously still training.
But his fights with Aang took their toll. Aang's fighting style involves a lot of dodging and avoidance; it's very easy to make an opponent look like a complete fool. And Aang did so each and every time they fought. Katara may have finished off his credibility, but it was already on life-support by then.
Zuko also had a few too many Komedic! moments, where he wouldn't just be defeated but humiliated. Like in The Warriors of Kyoshi, when you get a shot of Zuko drenched in water. It's a lot harder to see him as a credible threat at that point.
Zhao had problems from moment one. His biggest problem is that he didn't have a personality. Zuko was given backstory, which was able to sustain him through the times when he was getting beaten by Aang. You feel sorry for Zuko because of who he is. Zuko also had a real personality; his fierce determination was his calling card.
Zhao had none of that. He had neither style nor substance. He was just "the army guy;" he was the personal representation of the Fire Nation army (navy. whatever). Zhao never even got his own background music. He was utterly generic in every way. No backstory, no personality, nothing. He gained some of this towards the end of the season, but even that was too little, too late.
Lending credence to this theory is the fact that Zhao was involved in the events of Avatar Roku. Zhao was a one-season villain, so why bother having him involved? He ultimately contributed nothing to that episode outside of making Zuko look weaker. So why have a one-season villain there? Because, at the time, Zhao wasn't intended to be a one-season villain. He may not have been meant to survive the whole series, but I don't think they intended for him to die in season 1.
Avatar Roku was a big event for the series, putting a clock on the series finale. And if you have an important villain in the work, he should be involved in big events in the series. Like this one. Zhao hadn't been seen since the third episode; it was imperative for a long-term villain to be involved in a big moment, even if he didn't ultimately contribute much.
Having picked apart the season 1 villains, let's look at our season 2 villain. Her introductory episode is packed to the brim with style, character, badass, and most importantly, threat. We'll get into this more when we look at season 2's opener, but this is how you introduce a character.
Unlike Zhao, she gets her own theme music. And unlike Zuko, she doesn't share this theme with the Fire Nation; it's used for herself and herself alone. She even gets a little chord that comes up whenever she appears as if from nowhere (which she likes to do a lot) or is being particularly awesome.
More than that is how she fights with Aang. Despite not changing Aang's style one bit, Aang never makes her look foolish. When he dodges Zuko's attacks, Aang looks comfortable and confident, like he could keep it up all day. When he's dodging her attacks, he looks rushed and haggard. He's panicked. He's barely surviving, avoiding death by hook or by crook.
She loses, of course. But, with one exception, it is never a complete loss. Some damage is always done, some harm always inflicted, some forfeit always extracted. And she always loses with style, retaining her dignity. Beating Zuko merely required some skilled airbending. Beating her always requires effort, thought, guile, and occasionally some luck.
Or calling in a lot of friends.
Speaking of which, she gets a Gaang of her own. People who are shown to be competent in their own rights. They magnify her threat level as Aang increases the size and power of his group. It also shows off her character, as she's dealing with "equals," unlike Zuko and Iroh who clearly share a semi-parent/child relationship.
And there's one last bit of evidence. Our new season 2 villain uses the same face as the woman to Iroh's left in the flashback from The Storm. However, she would have been 3 years younger; she shouldn't have looked exactly like she did in the flashback. They spent time and effort making 13-year-old Zuko appear clearly younger, but not her. That strongly suggests that she wasn't an explicit plant so much as a nice face they drew on an extra and then decided to appropriate for the season 2 villain. Or perhaps someone (older) who had a different future purpose that they repurposed as the season 2 villain.
So, am I saying that the writers were just fumbling around in the dark, not knowing what they were doing? That they were incompetent hacks who shouldn't have been in the industry? That they accidentally wrote this critically acclaimed series?
Quite the opposite. My point is that the writers did something that unfortunately few writers are able to do. They were able to analyze their own work dispassionately, see mistakes they have made, and endeavour to correct them, as best as possible
Not many writers can do that. How many long-running shows have you seen that declined in quality despite having the same writers? That happened because they started believing their own BS. Their early successes made them think that everything they did was perfect. And with full Protection from Editors thanks to those successes, they started doing things wrong.
Making mistakes is human. Being inexperienced is human. Not correcting those mistakes is foolish. And even when they're writing crap, these writers are not fools.
What's more interesting is how they choose to solve these problems. Look at Zhao. They decided to off him at the end of the season, but they still gave him a personality. Not much of one, but they still spent time and effort doing so. They even tied some of that into the main story, with Aang meeting Zhao's former firebending teacher. The Gaang will even find that ancient library that Zhao ran across.
Not many writers would bother with that. Particularly for a character that's already destined to die in 7 episodes. But they did. They took what they had and used it as much as they could.