So, do you have an ATLA superhero AU? (Because Blue Spirit was totally a superhero identity, and I can see a lot being done with that)
1. When Mai was very little, she had terrible nightmares about a woman, made up of smoke and shadow. The woman would sit at her bedside and stare at her until she woke up, then the woman would reach out and touch her, and Mai would disappear. When she really did wake up, soaked in sweat and crying, she would have the strangest feeling that she had seen the woman before, in the real world, when she was awake.
Then, when she was twelve, still a child, but staring to look a little more like the woman she would become, Mai was standing in front of a mirror when it clicked. The woman whose face had been in her childhood nightmares was her own. She reached up in shock to touch her face, and disappeared into a roiling pool of shadow smoke.
Just as quickly, she popped back into existence and went to school, shaking, and terrified, with no idea what she was or what had happened.
2. The first person Mai met with powers was Ty Lee, who introduced her to Azula. Ty Lee can make up to six duplicates of herself, and Azula can summon lightning. Mai though has always suspected that Azula has another power. She has the best luck of anyone Mai has ever seen. The universe seems to bend around her to fulfill her desires.
Azula was in town with her father to find and recruit other children with powers into his new school. Azula told her all about her father’s special sensing equipment, and about what it’s like to be with kids just like them, and no, Mai, you’re not a demon, or a spirit, you’re just a little better than human, just like us.
This is not the same sell that Ozai gave to Mai’s parents, where he talked about academics and keeping their daughter safe from people who would use her. They sent her away to his academy, and Mai always figured they were happy to be rid of her.
3. Of course Ozai was the person who was going to try to use her. He wanted an army of special children, just like he was, just like children are, to overthrow the government and install himself as the superior dictator. Mai was something of a jewel in his crown. Her ability to materialize and dematerialize herself and anything she’s touching at will is a perfect supervillian power, and she was taken away for special training as a spy, thief, and assassin.
Through Azula, Mai also met Ozai’s other child, Zuko, who has fire powers, and who his father and sister generally viewed as disappointing cannon fodder. Eventually, Zuko ran away, found his uncle, and ended up becoming a superhero called the Blue Spirit, fighting to expose his father and his school.
4. Mai ran away too, later, after helping a captured Zuko escape from Azula. For a while, she did what she was best at, stealing to survive, and ignoring the world’s problems. But then she spotted Azula working to recruit more kids, feeding parents the same line that worked on her parents, and she just…
By the time Ty Lee ran away and tracked her down, she was already a full fledged superhero herself, calling herself the kemurikage after a story her mother told her as a little girl, after the nightmares mostly stopped. She and Zuko had even teamed up a few times.
5. Mai once dematerialized a person, a super soldier named Suki, who caught her robbing a bank. When she rematerialized her almost a month later, Suki was a little… Traumatized.