Sweet :-)

Brie strolled around the corner heading back towards high-school, cheesburger in one hand, shake in the other, and stopped dead in her tracks. The road ahead had been blocked by the TCPD. Two police vans and four cars, and around twenty officers, kneeled in cover with weapons trained on the bank, while what looked like a humanoid wolf in a cop uniform pushed a man into a van. That man would turn out to be a get-away driver, and his three companions still waited in the bank, with about 10 bank workers and 15 customers as hostage.
A shot rang out, then screams, and the whole mood changed. Brie could see it, somebody had died and the police were getting nervous.
She had to act.
Ducking back round the corner, Brie dodged into a back alley, took her backpack off, and began to change. White spandex pants were pulled on, skirt stowed away, vest removed revealing a red sports top, training shoes were switched for red combat boots, and lastly, she clamped on the blue belt and bracers. Quickly she stashed her pack behind a dumpster, and took a deep beath.
"This is it", she told herself, "still only 15 years old, and Brie girl, your gonna have to go out there and shine."
In daylight, with everyone watching, including the city news media. And a few journalists. And maybe other Heroes judging her moves.
Brie nearly had a panic attack, and took another deep breath.
She almost ran out of the alley, but then realised, "why run, this is it". Focusing her inner strength, she changed the gravitational focus of her own body, and lifted effortlessly into the air. Still not wanting to alert the crooks, Brie, now Britannia, landed on the roof top, and made her way running and flying from building to building, until she was behind the bank, and dropped down into its own back alley.
Britannia looked, in utter amazement, at the banks back door. Totally unguarded, by both police and crooks. It was as if the world had forgotten it was there.
And of course it was locked. The metal was old, grimy and dusty. The door probably hadnt been opened in years, and so she began excerting preasure. She pushed the gravity of the hinges backwards, and bit by bit, the frame began to creak. she mentally placed a gravitational cushion of the far side, gave one last strong push, and with a snap, the door came free.
Immediatly, the sound of falling brooms, dustpans, old shelves, buckets, bags of rubbish and metal filing cabinets filled the alley, as the old cupboard that housed the banks back door, fell into chaos. This was quickly followed by shouting from within the bank, and then silence.
Cleaing the clutter out of her way as quitely as she could, and found the opposite door in the cupboard, and this one would definatly open into the bank itself. she began to excert a tiny amount of gravitational force forward, probing the structure ahead of the door. Something was there, something solid.
It was a big row of metal filing cabinets! The fools in the bank blocked up the unused cupboard, and the important back door, with something to keep their old paperwork. more than that, Britannia could now hear the man on the other side of both the door, and those cabinets.
"Well, okay", she thought, "Your going to have to make a move".
Focusing all her defences inwards, Brie absorbed the movement of the air on her skin, she absorbed electromagnatism passing through her, the gavity of the planet acting upon her, dark matter and dark energy, everything. In a moment she went from being only invulnerable, to female figure of void hovering in the air. She felt the absorbed cosmic forces churn within her body, and then she pushed it all forward in a gravitational wave, no more than one meter ahead.
The door exploded and the metal filing cabinets shot forward at seven times the speed of sound. The bank robber was dead even before the metal hit him, his internal organs being liquified by the shock wave, and then the cabinets did hit him, and his bones became little more than dust.
Casually Britannia dropped back to her feet, and walked into the bank proper, no longer looking like a feminine black hole with anger issues. She could se all the hostages, each of them covering their ears, all of them had been temporarily deafened by her blast. In the midle of the room stood the last 2 bank robbers, trying to maintain order while suffering the worlds worst tinnitus.
Brie, simply smiled at them.
One shouted "A hero, kill the bitch", probably alot louder than he intended to, whilst his comrade, still deafened, looked confused. Then they both raised their shotguns and opened fire.
Bullets slammed into Britannia, one after another, and with each shot she felt her inner power grow just a little. When one of the 2 men stopped firing, and glanced at a hostage, she decided enough was enough. Changing the gravititational focus of the 2 shotguns, she lifted the 2 weapons in the air, pointing them to the ceiling. And there she held them, including the vaillains hands, now raised above their heads.
Brie looked around the 2 would be robbers, through the big glass windows of the bank, and waved to the police. within a few seconds, a swarm of blue clad men and women had charged into the bank, cuffed the 2 bad guys, and only then, she let the weapons and their arms go.
Before her stood a humanoid wolf, in a police uniform. He seamed both glad and angry, somehow at the same time.
"You're new, and young. Do you have a name"?
"Britannia", Brie paused, "you knew my father, he came here to help".
The wolf cops demeanor softened as he whispered 2 words to himself "past tense".
"Can I go" asked Brie, not sure what the procedure was "theres a guy back there, he got squashed".
"We know, and he'd already killed a hostage. Drop into the station when you get a chance, this week. Register."
"I will", replied Brie.
"And Brie" said the wolf cop, "Make your fathers spirit proud".

That is awesomely super, or super awesome. Maybe both.
If i can add one change, no white top. (Its the red sports top and skin).
And I must add...
I love the boots, and the mask. I had not put the mask in her description, but after seeing your picture, I may have to add it.

I understand that. To tell you the truth, Britannia (as I played her in CoH/V) was never defined as a teenager. Its only when I adapted her background to the high school that she became 15, and I had not realised that I needed to make a slight costume change. Mind you, teenagers these days...lol
Since this is the case, I'd probably drop the description of the red sports top (which would be unseen under the white jumpsuit), and put some sort of emblem on the chest of the jump suit instead. Hay, thats upto you too. I still love the pic.

From Ari (and her team), I'm getting a covert ops/swat vibe, and there is a hint in your story of gifts from Major Centurion.
This leads me to a 'Batgirl' vibe for Ari, just as Brie has the 'Supergirl' vibe.

You know, if we can get a few others in here, we could get a 'teen titans / young justice' thing going on.

Enter, Team Green

Titan city held many wonders, and many mysteries, powers great and small, and miraculous events made the news on a daily basis.
But to balance this out, there was the high school cafateria. Brie looked at the slop on her tray, and for the first time in her life, missed the school dinners of England.
Brie sat alone. Ari and the boys were out somewhere, and the rest of the school viewed her as an exchange student, it also didnt help that she was somewhat prettier than the schools 'popular girl', who in the past few months had ran a bitchy hate campaign against her.
And of a sudden, Brie's contemplation of lunch was brought to an abrupt stop. Something, was getting in her hair.
Slowly she turned, and there was Jessica, the polular bitch, and her two sidekicks, Joan the moan and Melissa. Jessica's tray was empty except for 1 pot of yogurt, which had just been poured into Brie's hair.
"Opps", purred Jessica, "I slipped, I'm sooooo sorry". The rest of the cafateria started to laugh.
Brie fumed, but did her best to hide it. She could just crush the girl, but that would be both morally wrong, and would blow her cover. She had to do something.
"You know", said Brie, "You shouldnt cross us English girls, we all have magic powers, I could curse you".
In any other city, a statement like that would be laughable, but not in Titan.
"You dont have the chops you silly girl" said Joan.
"You, magic, dont make us laugh", added Melissa.
Brie stood up and faced the three of them "I curse you Jessica, to crap your pants"!
It didnt take any effory at all, Brie focused a tiny portion of her gravitational telekinesis, and squeezed down Jessica's bowls.
The effect was immediate. There was a momentary yelp of pain, then a sound, and then a stink, and everyone nearby saw the liquid feces running down Jessica's legs.
People dashed backwards, as if the brown pool on the floor was radioactive, and even Joan and Melissa took a step forward and then they changed.
The eyes of the two sidekicks flashed bright emerald green, they raised their hands, and from Joan came a steam of green lightning, while from Melissa came a flow of toxic green fire. Somewhere behind them, Jessica cried in shame and disgust, and then snarled "burn the bitch".
The twin blasts hit Brie, and didnt stop. By instinct she held her hands before her, but it didnt help. Fortunatly, her other instancts had kicked in, and her kinetic defence was absorbing the energy of fire and lightning, if only just. There was flashes and moments of pain, the 2 bolts of power were at times beating her defences, and Brie knew she couldnt hold this forever, at some point, she had to do something drastic. She noticed, behind the 2 sidekicks, Jessica had transformed, he body was now pure crystal emerald.
With one hand, Jessica ripped a metal railing on a fire door free of its steel bolts, and walked towards her.

And at this moment, Ari, Kevin, and Amir, entered the cafateria.

Enter, Team Green
Part 2

And at this moment, Ari, Kevin, and Amir, entered the cafateria.

Brie glanced at her three new friends. Something was going on with them, something covert. She didnt know what it was, but Brie trusted that it was important, and that it had to stay secret. She turned back to Jessica walking towards her, metal bar in crystal hand.
It took no effort, as Jessica passed Joan and Melissa, Brie simply quadrupled the gravity under the three of them. Immediatly the twin streams of green fire and lightning stopped, as both Joan and Melissa collapsed to the ground.
"Your 7 stone frames, just became nearly 30, and I dont think you have the muscles to support that".
"But I do" purred Jessica, "super strength, part of the package in the emerald body".
"Yeah, I guess" replied Brie, and with that, altered Jessica's gravity, and levitated her back across the room, suspending her in the air.
"But all the strength in the world means nothing, if you dont have purchase"
Brie smiled at Ari and the boys, and took note of the other students arrayed around the edges of the room.
"I am Britannia"
"Stop this Brie", the call came from Ari, it was a request, not a command.
"You know i could crush their bones, or pull their guts out, or throw them into the sun".
"And you would become them, you become a bully, abusing your power"
"No", said Brie, "Of course not".
With that, brie let the gravity manipulations drop, and let the three girls go. Jessica dropped to the ground, while Joan and Melissa stood up.
"I just needed them to know, what I could do, if I was them".
"But your secret is out now, everyone is going to be watching you"
"Thats right". Brie smiled, and threw Ari a wink "They'll be watching me".

Whatever graphics program your working, your results are excellent. Mad skills on display.

Dude, I'm waiting for the next update on Ari's story, arrrgh, I dont want to totally own your thread, so I cant give the third and final Britannia story until you add yours!