It’s a true battle of fire and ice in the Season 1 finale of Avatar: The Last Airbender. On one side, there’s Avatar Aang (Gordon Cormier), Katara (Kiawentiio), Sokka (Ian Ousley), and the Northern Water Tribe. On the other, there’s the Fire Nation forces, led by Prince Zuko (Dallas Liu), his uncle Ihro (Paul Sun-Hyung Lee), and Commander Zhao (Ken Leung). The Fire Nation seems determined to take the Northern Water Tribe’s capital of Agna Qel’a — and defeat the Avatar once and for all — no matter who dies on their quest for world domination. Some are even willing to sacrifice the primal forces of nature, like the Moon Spirit, to do so. 

You may be asking yourself, “Why?” Showrunner and executive producer Albert Kim reveals that the answer might be more complicated than you think. Fire Lord Sozin (Hiro Kanagawa) started the Fire Nation’s war over 100 years prior to the events of Avatar due to “his own personal ambitions and agenda,” Kim explains. As we learn in the mid-credits finale scene, Sozin’s Comet, which is named after the previous Fire Lord, is now on track to return. But, Kim explains, everyone might not be following Sozin’s agenda these days. 

“At a certain point, war has its own momentum and you start to forget why it started in the first place, and that’s one of the themes we hint at,” Kim tells Tudum. The Fire Nation might say it’s ensuring an era of peace by bringing the world under its rule. But “you can tell that [someone like Iroh] has his own doubts about those reasons,” he says.  

Although the Fire Nation’s motives may be murky — even to its own citizens — the destruction it causes isn’t. By the end of Avatar: The Last Airbender Season 1, the city of Omashu has fallen, one princess is sacrificed, and countless people are dead. Kim is here to explain every step of the journey. 

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Wait, what happened at Omashu?

The Fire Nation loves a switcheroo. Throughout Season 1, it appears as though its military is determined to crush the peaceful Northern Water Tribe. But the Fire Nation fails. Although there are many casualties on both sides, Aang and his allies ultimately win the battle. As the Aang gang takes in the aftermath of the bloodshed, viewers get a glimpse of what’s happening at the Fire Nation palace. Fire Lord Ozai (Daniel Dae Kim) reveals he isn’t upset that his army couldn’t conquer the North. 

Because the battle at Agna Qel’a was a distraction. “[The writers] really did a good job with that cliff-hanger by creating a sense of urgency,” Daniel Dae Kim tells Tudum. “I thought that was really important for the storytelling and where it’s about to go.” 

Ozai actually had his sights set on the Earth Kingdom all along — and his daughter, Princess Azula (Elizabeth Yu), has taken the city of Omashu. Aang’s old friend, King Bumi (Utkarsh Ambudkar), has been taken prisoner. “One of the things we establish in this world is that the Earth Kingdom is still fighting back against the Fire Nation,” showrunner Kim explains. The Earth Kingdom cities of Omashu and Ba Sing Se had managed to “hold out” against the Fire Nation for over a century. And now one of them has been sacked. 

“That’s a major development in the course of the war. It means that only Ba Sing Se stands [in the way of the] Fire Nation ultimately conquering all of the Earth Kingdom,” Kim says. “It signals a shift in the power balance of the world and indicates a much bigger threat for the future.”

Does that make Azula our new big bad? 

While Zuko flees the battle at Agna Qel’a bruised and bloody in a tiny kayak, his sister, Azula, ends Season 1 basking in the glory of success. She’s the one who led the Fire Nation to victory in sacking Omashu. The last time we see Azula, she’s standing in front of cheering Fire Nation soldiers as the Fire Nation banner is unfurled on the walls of the Earth Nation metropolis. Even Paul Sun-Hyung Lee, who plays Zuko and Azula’s uncle Iroh, was thrilled by the surprise. 

“Always leave the audience wanting more!” Lee tells Tudum. “I just had chills seeing Lizzy as Azula. You’ve got King Bumi in shackles, and it’s just like, ‘Oh, there’s so many cliff-hangers.’ ” 

Kim says Season 1 serves as a “bit of a prequel” for Azula. “Fans of the original series will know exactly the kind of character Azula will grow into,” he says. “We’re trying to tee that [evolution] up a little bit in Season 1.” So Kim and the writers focused on “showing how she fits in her family and that complicated dynamic that exists between them.” 

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What exactly is Whalezilla?  

Although Ozai’s master plan focuses on Omashu, a lot of scheming also went down in Agna Qel’a. Zuko, Irho, and Zhao descend on the city with different aims. While Zuko wants to capture the Avatar, Zhao eventually admits he has much bigger plans: He wants to kill the Moon Spirit, thereby eliminating the powers of every waterbender. Zhao is convinced this maneuver will make him a legend and allow him to become the Fire Lord. 

Luckily for Zhao, he makes it to Agna Qel’a on the one night of the year when the Moon Spirit and its corresponding companion, the Ocean Spirit, take physical form as koi fish in the Spirit Oasis. Zhao uses Avatar Kuruk’s (Meegwun Fairbrother) knife to kill the Moon Spirit, causing the remaining Ocean Spirit to be filled with rage. Aang, using his Avatar abilities, merges with the spirit, creating a brand new creature the Avatar team lovingly calls Whalezilla.  

“We knew that we needed to have this epic finale, and it culminates in the creation of this creature,” Kim says. “So we did everything we could creatively to build up to that storyline and make it seem like the inevitable conclusion to Aang’s Season 1 arc.” 

While the team wanted Whalezilla to terrify everyone in its wake, they also wanted to zero in on the emotional stakes of the creature. “The Water Tribe citizens all bow down out of respect, and the Fire Nation soldiers flee in fear,” he points out. Then there are the reactions of Aang’s loved ones, who are terrified he has been lost to Whalezilla. “Katara desperately wants to reach Aang,” Kim says. “So she can look past this terrifying creature and see who’s at the heart of it, which is her friend, and she needs to save him.”

The power of friendship brings Aang back to Katara, Sokka, Appa, and Momo. Now Aang is prepared to continue on his path as the Avatar. 

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Is Princess Yue dead? 

Kim confirms that Yue (Amber Midthunder) has “given up her own life” to save waterbenders worldwide — and the balance of nature. Once Zhao kills the Moon Spirit, and Aang becomes Whalezilla, Northern Water Tribe princess Yue sacrifices herself. She wades into the Spirit Oasis pool, which is the “source of all spiritual powers in the north” according to Kim, and allows herself to become the new Moon Spirit. 

To understand how this transformation is possible, look at Yue’s history. As a child, she was very sick but was saved by the Spirit Oasis through water healing. “She had the spirit of the moon essentially transplanted within her” at that time, Kim says. That’s why, he explains, Yue was still able to do a bit of icebending when the moon disappeared from the sky. Every other waterbender completely lost their powers. 

“That [piece of the Moon Spirit] is what she’s returning in order to bring the moon back to the world,” he says. Yue is lost in the process, but the moon returns. 

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Is Commander Zhao dead? 

Tensions are high between Prince Zuko and Commander Zhao throughout Season 1. Their animosity comes to a head with a fight during the battle at Agna Qel’a. Between firebending blows, Zhao divulges that Zuko’s mission to find the Avatar was “a sham,” and Azula was Zhao’s ally in undermining Zuko all along. Then, when Zhao attempts to kill Zuko, Iroh saves his nephew. Iroh sets Zhao aflame and careening into the water below. But is Zhao actually dead? 

“Zhao’s arc in Season 1 is definitely over,” Kim says. “As a villain, he has been conquered. As to his ultimate fate, it’s left a little bit open-ended. It’s meant to be a little bit of a mystery.” 

What is Sozin’s Comet? 

In the mid-credits sequence, Ozai’s spiritual advisor, the Great Sage (François Chau), tells the Fire Lord that a rare cosmic event is on the horizon. A representation of a comet appears over the Great Sage’s globe. This is Sozin’s Comet, and it’s returning “soon,” the Great Sage says. It’s named after the Fire Lord who began the war over 100 years ago. 

Is the comet good for the Fire Nation? Is it bad? Well, to quote Azula, the real question is: “What’s next?” 

Will there be an Avatar: The Last Airbender Season 2? 

Yes! Avatar: The Last Airbender has been renewed for a second and third season, which will bring this story to a dramatic conclusion. 

Additional reporting by Christopher Hudspeth. 

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