If you ever need to narrow down to just one reason why you love Avatar, have defended it to be one of, if not the best show ever made, flaws and all, I believe the best two moments to narrow down are two scenes in The Storm and The Avatar and the Firelord.
In The Storm, as Aang is reliving his biggest mistake, drowning in guilt, Katara comforts him by telling him that his mere presence is what keeps people going, what keeps the soldiers fighting. He gives the world hope.
On the other hand, Zuko, after being burned and tossed out of his nation, the promise of the throne, and most of all, honor, he has convinced himself that somewhere out there, there is a normal, a way to get the world to look at him and feel pride over their leader. Iroh, after his account of the events that had unfolded, immediately denounced any normal that can ever happen, but looking for the Avatar, the belief that delivering him will suddenly fill his father with admiration and respect… that gives Zuko hope.
The same word, same sentiment, that Aang gives hope to someone, conveyed in both a hopeful and tragic way… This is the strength of the show, the duality between Aang and Zuko has always been the consistently most prevalent factor in the show. Now, let’s skip forward a few seasons later.
A lot has happened now. Both Zhao and Zuko got dethroned by the new antagonist, Long Feng, who was further demolished by Azula. Zuko went through layers of change, of a broadened horizon in the Earth Kingdom, but still chose to betray Iroh, deciding in the moment of truth that he can, in fact, bury empathy and respect power above all.
Now, the next episode highlighting the duality of these two is The Avatar and the Firelord. As it turns out, generations ago, Roku and Sozin experienced an entirely reversed arc in contrast to Aang and Zuko, who saw themselves starting out as best friends, only to let the power that almost consumed Zuko take full effect on Sozin.
As the episode progresses, with each scene shared between the two, we are waiting for the other shoe to drop and Sozin to lose this strong sense of morality and empathy that has marked him forever. As we see, the beginning of the end was a simple… observation, fueled by ambition. This thing, the Firelord’s lifelong friend happening to be the Avatar? This is not an opportunity that the world has ever seen, or will see again.
After Roku’s refusal, Sozin probably had a long process of self-reflection, and from the position he was standing at, he had no reason to force himself to understand Roku’s argument. Sozin is the leader of the most prosperous and advanced nation in the world. If he wanted to, he can very well wage a war over the world and catch them blindsided. Even as children, he would outsmart Roku, the unconfident, shy kid. He was just declared the Avatar long after Sozin knew him, but Sozin himself was always destined for power.
At the twilight of his life, Roku found himself on his knees, moments before a wave of ash and lava engulfed him, with his hand being rejected by Sozin.
Now, let’s see Zuko. Do you remember how he reached his hand out to Zhao, much like Roku did, to save him, only to be rejected as well. For Zuko’s story alone, this was another crushing moment, that even trying to save his mortal enemy, he faces rejection. Over and over. But once we learn how Aang and Zuko reflect the two who came before them, we can feel a sense of victory for Roku, simply because Zuko walks the line between the two.
Zuko’s confrontation of Iroh proceeding the episode is one of the most powerful scenes in the show. The lighting and cinematography portray Zuko as the one behind bars, the slow reveal of his real ancestry, and the way one half of his face is covered when Iroh reveals his two great-grandfathers.
For Zuko, this entire story is this conflict, about corruption, Roku’s red dragon who will redeem him, or Sozin’s blue one who will consume him. As the episode concludes, we are left to remember that the sweet and empathic Sozin is the one who devolves into the genocidal dictator. One day before The Day of Black Sun, Zuko gets to relive the total corruption of the throne through his father’s genocidal ambitions, as he is left sitting on besides the throne, some day to follow in this legacy.
You could even argue that his time in the Earth Kingdom and his uncle gave Zuko an advantage of sorts, one that the previous ones did not exhibit. Being corrupted to your core is best exemplified through the prodigal child, one of the most tragic characters in the show, a 14 year-old girl.
While both Sozin and Ozai were shown to be fully-developed adults when their evilest of intentions were witnessed by us, every horrible action by Azula, from ambushing Iroh to murdering Aang, we see her do it and completely forget her circumstances. She is ruled by fear as much as she controls it. When she is defeated by Katara, outwitted by a simple technique, she just lies there, crying, maybe even for hours, like the little kid she is, having lost... well, everything. Fear, insight, fighting abilities, cunningness, the throne, everything she was entitled to, all of it to her pathetic loser of a brother and a peasant.
Now, for Aang, Roku’s tale was less of a cautionary and more an empowerment of his own beliefs. He didn’t see the pragmatism in killing Sozin before he could backstab him. Think about it. Sozin killed all of his people, destroyed his history, and pushed him into a universal role he despised, but after everything, he did not see people marked by their scars, their actions, but as vessels for morality, who can be emptied out and become someone else.
And you know what? Aang's beliefs weathered the finale. Both their stories collide thanks to Zuko, his own action and acceptance of who he is, not who he thinks he is supposed to be. This series of actions is, as quoted by Iroh, what will fix the mistakes made generations ago, and Aang, as Roku quoted, made sense of the past to bring peace. In the end, we did get to see The Avatar and the Firelord teaming up to grab the opportunity the world has only seen once before.