Days after he returned to the Fire Nation felt like years, but seconds all at once. When he got there, ever moment felt like he'd never left. Like the world stopped when he left and resumed its spinning when he entered the Nation again. But at the same time, time flew by so quickly. Days passed quicker than he could keep track of them, and he could scarcely remember it'd been five days since the Crystal Catacombs incident. But he wasn't thinking about that so much. His time with Katara was pushed to the back of his mind, and he was enjoying himself. A prince again. A loved, admired prince that so many people looked up to and liked so much and catered to him; it was such a change from being on that ship with Uncle for so long.

It wasn't until a royal meeting of course, did things begin to change. He hadn't been notified of this meeting until Mai mentioned that Azula was attending. Zuko, of course, wanted to know what the meaning of all this was, and he was told quite a lot of nonsensical things by his sister, but was convinced not to attend. It wasn't until he was summoned to the meeting, saying that they would wait for Prince Zuko's arrival, that he left to for the meeting. He sat beside his father, a place he had for so long hoped to be. He was at his right hand. He was special. He was important. He meant something to his father. And he didn't think he'd ever feel this way. As the meeting carried on, Zuko paid attention. Usually, he wouldn't intently listen so much, but after missing so much he didn't want to miss another word. After all, what if he WAS back into the line of succession? He had to know everything he possibly could.
And that was Ozai and Azula's intent to burn so many places. To set them on fire and have them reborn from the ashes, like a Phoenix. Hence his fathers new title, the Phoenix King. Zuko had remained silent (knowing he had a permanent reminder from when he last spoke out of turn at one of these meetings), but thoughts rushed in his mind. Thoughts about how this was crazy. About how his father couldn't possibly be serious; how could this be 'sharing the Fire Nation's greatness with the world'? The world was being destroyed, so that the Fire Nation could rule over them in an oppressive monarchy! This wasn't what he wanted to hear, but thinking about it, he didn't really expect anything much different of his father and his sister. He should've known. And before, he would've been on board. He would've done anything to win over his fathers affection and to be the perfect Prince of a son that Ozai had always wanted. But it wasn't him. When the meeting ended, and he exited, he realized he truly wasn't himself in there. This wasn't what he wanted, and this wanted what he needed to be doing. It wasn't his destiny. His destiny was something much different from this. He wasn't sure what he needed to do exactly, but he knew this plan that his father had, this horrible, oppressive idea of a new world, wasn't his destiny. He wasn't destined for this path. He needed to make his own path, to carve his own name, not let his father do it for him. He needed to visit Uncle. He needed guidance.

After what felt like thousands of visits to Uncle and only to have a final one successful, he realized it was The Day of Black Sun. During he eclipse, all firebending would be rendered useless. Today was also the day of the invasion. Azula had informed him that they had planned an invasion, which they wanted to be a surprise. But Azula had found out about it through her many sources (likely by threatening someone), and knew the attack was coming. But Zuko had other things to worry about.

Uncle's words were still buzzing in his thoughts

"What happened generations ago can be resolved now, by you. Because of your legacy, you alone can cleanse the sins of our family and the Fire Nation. Born in you, along with all the strife, is the power to restore balance to the world."

His maternal great grandfather was Avatar Roku, as his paternal great grandfather was Fire Lord Sozin. Their conflicting minds and ideas, their want to either win the war or stop it all together, it was what conflicted Zuko so much. It was what Uncle explained to him. His great grandfathers' conflicting and differing ideas and minds was what was doing this to him, and it was time he put a stop to it. It was time he stopped choosing the wrong choice, the choice he would regret and be shameful of later. So many times in his life did he make the wrong choice, and now he needed to make up for this. Anything that would victimize a person, even just one person, it wasn't right. He was going to be the next Fire Lord, no matter what the succession line said, he couldn't let Azula's insane, tyrannical mind rule over the most powerful nation in the world. They nations needed to be four once again, equal and no longer at one anothers' throats. The war needed to come to an end. He was the legacy born with both the want for the war and the demise of the war, and he had the power to stop it or fuel it. And he couldn't go another day without trying to finally put and end to this war.

The war that took away his childhood, and his mother. The war that took away her mother.

Katara

She was still out there. She was stopping the war, right now. As he was reading, the invasion was bustling outside. And Katara was there. How could he have let it slip his mind? And finally, he realized, it was because he couldn't afford this right now. All these distracting thoughts, all this focus on her, it would stop him from doing what he needed to do

He needed to stand up to his father

Finally

No longer could he submit to being such a dispensable ingredient in his plans, and his plots to rule. His father tempted him and baited him with the return of his honor in order of Zuko doing whatever the Fire Lord could cook up. But that was no more. He already had his honor back, and he regained it by realizing what he needed to do. He regained it by realizing that this war was not for the good of any nation but the fire nation. And even at that, the other nations doled out much deserved hatred to them, and Zuko didn't want that. His nation shouldn't continue to be seen this way. No one could simply give him his honor; it was something he needed to earn. And the decision to do what was right, to finally end this war and make the right choice for once was what would make him an honorable person again.

And he left for his father's quarters, protected until after the eclipse

It was time he regained his honor

No

It was time he informed his father that he was already more honorable than he would ever be, and that he realized his path and his destiny. He learned his way again, even after it was lost for so long. Uncle would be proud of him, even after all the times he messed up Uncle couldn't hate him could he?

Whatever his Uncle thought, Zuko knew that he was going to play a new part in this war

The part of the banished Prince who aided the Avatar and took back his throne, and restored the honor to his nation, for it was the one that needed it the most