Ozai was never content to just let his older brother have the throne, unfortunately he didn't have much of a choice, he already had everything, so why should he have this?

He had the best toys.

He had Father's admiration. Not that he cared, but it played a major role in who got the crown.

He always got the last pieces of desert, not that he wanted some stupid tea and cake anyways, he wanted it simply because others said he couldn't have it.

It just wasn't fair, Ozai had always prided himself in his firebending. That was until he was forced to watch his older brother during some dumb training session one day. It was a day he would rather forget, his Mom, annoyingly persistent as ever got his Father to agree to drag him all the way out of the capital far away to some secluded royals only school. He most certainly wasn't jealous Iroh had gotten to go there and he didn't. Ozai had of course heard rumors about how his older brother's Firebending training was going, he didn't believe it, rumors always seemed to turn flesh and blood into terrifying unimaginable powers.

Ozai never stuck to rumors, they were vague and uninformative at best, flat out wrong and exaggerated at most.

Sadly these rumors were wrong.

If Ozai was considered a prodigy he was nothing compared to his brother, then again his brother was 10 years older than him.

Iroh wasn't just good, he was Amazing.

That wasn't the point though, his fragile ego had been bursted and he sought to become more powerful than his brother.

He skipped the basics trying to speed his way through his training and just managed to look like a fool, tripping over his own 2 feet like a 2 year old, burning himself up slightly in the process luckily he was only 8 at the time so it was amusing rather than degrading.

That didn't deter him from his strive for perfection though.

He was stuck being 3rd in line for the throne after his brother had his own little brat. Little Lu Ten, loved by all, it made him want to hurl. If he ever fell in love and had kids, he would train them to carry the family legacy, if they didn't, there would be consequences. Simple as that. His kids would be amazing and great, and loved, because they were amazing and great, not because Little Lu Lu was good at looking "cute."

He never did marry for love, Iroh obviously got everything he wanted, he married the girl he loved, got their fathers praise, and what did he get stuck with? A dirty peasant girl that they somehow said was Avatar Roku's daughter.

Still never once did he complain! He understood that his children would rise to bring his country great honor, perhaps this was Agni showing his favor, having him marry and have powerful children even if it wasn't for love, who cares he had to break up with the girl he liked just to marry some nobody, this was Agni showing his blessings.

Power was much more important than some dumbfounded love anyways.

Some days he did wonder what would have happened if he had been able to marry by choice.

He never once disrespected his wife, he was always good to her, it was still a loveless marriage, he had tried his hardest but his wife still seemed infatuated with this peasant boy she left behind, what did that peasant guy have that he didn't!?

Honestly. It felt like he was always getting the short end of the stick. He'd have to change that, didn't it say that his children would preserve the legacy of the Fire Nation for years to come, blah blah blah blah…

Worth a shot, besides, Lu Ten was already growing fast. He wasn't going to lose to his brother, even if by now he had figured out that the whole sibling rivalry was all in his head, which was slightly degrading but he was over that.

Ozai was on to bigger and better things than making his sibling mess up on purpose, or fighting over the dinner table.

You would think having children would bring them closer together, she even had a boy as an heir, for a while they were happy, well as happy as they could be.

They went on trips, and did all the things a family did or whatever.

Apparently he didn't have Agni's blessings, the boy turned out to be a nonbender, by 6 years of age he hadent even bent a single spark, while his sister had produced them at age 3.

Also Zuko was just an idiot.

His daughter, Azula on the other hand as they had named her was a bright talented young girl, and what was better, she did everything she could to please him. Zuko meanwhile was a weak non bending boy who was honestly a lost cause, how disgraceful would it be to have your firstborn child a nonbender, the first nonbender in over a century.

Any time he had to attend family dinners or be in the same room as his nonbending son, making speeches or what not he silently panicked wondering when someone was going to point that detail out.

He'd never admit that though.

Azula, well she was born lucky, truly a prodigy, a useful tool.

By year 7, Zuko had finally produced sparks, when all the other young boys had already produced them, but it was better than nothing, perhaps his late start would push him to work harder.

Instead Zuko spent his free time feeding the turtle ducks in the palace gardens, he felt an urge to run down there and burn every one of them to a crisp, to listen to their dying screams and to feel the sense of power.

How are you supposed to learn if you are distracted after all? Perhaps he should make Zuko do it himself, that would be much more impactful.

Unluckily it wasn't his palace, and his father always had a strange fondness for them too. One day though… one glorious day. When the place is all his, those stupid turtle ducks would be gone.

Later he forgot about that minor little issue when his situation with his wife only grew more and more distant, she had a distaste for his methods of training for ages, it was easy enough to forget her though, they rarely talked nowadays, they both had their children there was a clear line between them.

He had Azula.

She had Zuko.

Perfectly balanced.

And he was determined to show Azula, his daughter what true power was like, unlike her weak minded brother she was destined for great things. If it meant driving her and her brother apart so be it, siblings were overrated anyways.

By the next year his wife was getting even more unbearable, he took slight satisfaction that Iroh's wife had died.

They never could see eye to eye on things. She wanted their children to be soft turtle duck feeding nobodies, like most, she couldn't understand his vision. A glorious future where the world was his for the taking, everyone was there to amuse him. Monkey's trained for a circus and one wrong slip up…well it wasn't going to be pretty.

Where he was on top, now, and forever.

So he and his most loyal allies sought to find the right time to strike.

Life was going fine until he realized how traitorous his wife was, dare claiming that Zuko was not his child? Obviously he had not drained the fight out of her properly, she needed to know the consequences of her actions.

After that day he stopped treating Zuko with even a hint of kindness, it was almost too easy. Almost. He was already the failure of the family, perhaps he didn't want Zuko to be his son either.

He sent assassins disgusesed as Earth Kingdom soldiers to kill his brother, they were incompetent failures they only managed to kill that brat Lu Ten. Later he tried to murder that peasant in spite at the other's failure, they failed as well.

Still it gave him a claim, especially when Iroh just gave up and returned. Surely his Father could see who was the better child by now, especially with Iroh showing his true colors. A weak emotional coward.

"A real general would burn Ba Sing Se to the ground," he had said to his perfect copt, after they heard the news, later that day as he passed by a room he heard a snarky voice say dismissively, "A real general would burn Ba Sing Se to the ground, not lose the battle and run home crying,"

I tried to make Ozai both have some realistic hopes and expectations, making him a bit more human, but also making it undoubtably clear he's an awful awful person.

Ozai smiled, however cold it was. At least one of his children had picked up something. It was in that moment he made his choice, Azula would be better than Zuko could ever be.