one of the most common anti zutara arguments i see is that Zuko would have taken lightning for any member of the Gaang. i agree completely.
but would Azula have targeted any other member?
i actually donāt think so.
Azula is calculating, manipulative, and an expert on how to upset her brother. She reads and analyzes each and every thing that he does.Ā
When Zuko shows up in the Catacombs Azula doesnāt know whose side Zuko is going to choose. Her face says that sheās calculating his next move.Ā
And then Zuko decides to attack Aang.Ā
Azulaās satisfied smirk says sheās pleased, but not that she was necessarily expecting it. But look at Katara, sheās actually kind of surprised that Zuko went after Aang. And then the fight ensues.Ā
Iāve said it before, but Zuko doesnāt attack Katara until Azula is in serious danger. She sincerely thinks that Katara is about to smash her into the ground. Why is that? Very little manages to unsettle Azula; this is probably the most frightened we see her up to this point. Being at Kataraās mercy scares the crap out of Azula, even after Zuko seems to have chosen Azulaās side against the Avatar.Ā
Maybe she doubts Zukoās abilities, maybe she understands Kataraās power.Ā
Or, maybe she doesnāt think Zuko will try to stop Katara.Ā
But then Zuko does step in to break Kataraās hold on Azula. He doesnāt strike Katara, even though he has a clear shot at her and it would be the more strategic move. He only breaks her grip on Azula.Ā
Another calculating look from Azula. Yes, her brother came to her aid against the waterbender. But did he attack her? Not quite. Attacking Katara directly would have accomplished the same goal as severing her water tentacles, but Zuko chose the option that wouldnāt harm Katara. He had just gone after Aang relentlessly, but he hesitated to use such violence against Katara.Ā Azula wouldnāt fail to take note of this.Ā
And Azula hears KataraĀ angry with Zuko. Thinking he had made a change, become a better person (by Kataraās standards). Azula would be able to gather that somethingĀ had taken place in the Catacombs when they were together. Azulaās the one who put them in there.Ā
The next time Azula sees her brother heās joined up with the Gaang. During this fight sheās only really gunning for Zuko. She could go after Sokka or Suki in an attempt to upset Zuko, but she doesnāt. Azula doesnāt see the value in sending either of them careening into the boiling lake.Ā
The next time Azula sees Zuko, she sees this. Theyāre both falling to their deaths and itās the waterbender who is up in the saddle, reaching out to Zuko. The same girl who had thought Zuko had changed before he chose Azulaās side in Ba Sing Se. The same girl that Zuko had been trying notĀ to harm last time they fought.Ā
SheāsĀ the one who isnāt clinging to the saddle for safety, but risking toppling off the bison to save Zuko.Ā
And Azula says interesting indeed.Ā
Azula doesnāt witness this ^^ particular tenderness, but she sees a flicker of it when these two turn up for the Agni Kai.Ā
Thatās why we see theĀ āI know more than you doā smirk when Azula takes aim at Katara. She has spent her whole life finding ways to hurt Zuko. She knowsĀ that Katara in particular is a weakness for Zuko. She saw it when they were in the Catacombs.Ā
Zuko is grounded and confident today when theyāre fighting. Katara is by his side and apparently she was right about Zuko changing. And Azula sees that Katara has helped make Zuko strong. Sheās been there for him. Saved him. Supported him. Encouraged him. Katara was the one who already believed in Zuko back in Ba Sing Se, betrayal aside.Ā
Thatās why Azula wants to kill her.Ā
Iām going to circle back to something else to prove this point. In The Chase, we see the first time that everyone else unites against Azula.Ā
Azula realizes then, too, that she is outmatched. And she pulls the same tactic in The Chase as she does during the Agni Kai.Ā
She goes after someone who loves Zuko, who believes in him and supports him. Someone who believes that Zukoās strength lies in his goodness.Ā
Azula goes after Iroh because she knows how much damage it will do to Zuko. More damage than could be done by killing him. It will break him enough for Azula to defeat him.Ā
Prior to his return, Azula sees Zuko hesitate about taking her side in the presence of two people: Iroh and Katara. Azula has exclusively seen these two as a threat to Zuko siding with her. Azula has seen firsthand that, for some reason, Katara makes Zuko hesitate.Ā
Azula thinks that sheās going to kill Katara. She doesnāt think for one second that Zuko is going to move faster than lightning to save Katara
But he does. And he has the same horrified look on his face as he did when Azula nearly killed Iroh. Because Azula was right, as usual.Ā
Azula comes completely unhinged after she hits Zuko because she absolutely intended to kill Katara, not Zuko. (Despite it all, she cares about him) She had calculated that Katara would matter enough to Zuko for her death to change the tides and for Azula to win the Agni Kai. But she micalculated. Again. She hadnāt anticipated that Katara dying would scare Zuko so much that he would die in her place.Ā
Azula isnāt stupid. Even crazed, sheās calculating. Sheās seen evidence that Katara will make Zuko hesitate. Like she knew attacking Iroh would completely distract Zuko.Ā
There is only oneĀ member of the Gaang who Azula has this impression of, and itās Katara. If any other member of the Gaang had been waiting in the wings I donāt think Azula would have broken the rules of the Agni Kai. She wouldnāt have been able to bank on it being enough for her to take Zuko down.Ā
But Azula knew that, with Katara, it would be.Ā
Whatever has gone on between these two is strong, and Azula knows it.Ā