Fluttershy kicked off the story first.
“I was at home getting ready for bed when Rainbow Dash showed up at my house. She told me about the fire at Town Hall and about needing Pegasi to start a tornado to put it out. She didn’t tell me about the Ursa, probably knowing I would have run away.
“I had just started making my way to the Town Hall when I came across said Ursa… just as it was bringing a paw down on you, Derpy, and Dinky. You shouted something, and suddenly there was far too much light to see much of anything.
“That’s when things got strange.”
Fluttershy frantically rubbed at her eyes, trying to get them to stop stinging from the impromptu flash grenade that was Twilight Overdriving. Not that she knew that yet.
When she could see again, it was to the jaw dropping sight of Twilight surrounded by a veritable hurricane of magic. The Ursa Major was thrashing around in the air directly above Twilight, held aloft by a thick haze of purple magic.
Suddenly, the magic around Twilight compressed into a brightly glowing circle that floated around her horn. Symbols and markings Fluttershy had never seen before filled the circle. Then, swinging her horn upwards, Twilight pointed the circle and her horn at the Ursa.
“Magic Missile!” There was a pulse in the air, and then a massive beam of magic exploded from her horn, hitting the Ursa Major and completely overwhelming it. After a moment, the magic died down.
Fluttershy realized her jaw was hanging open just as Twilight collapsed, unconscious.
Twilight groaned. “Stars, no wonder I feel like crap,” she grumbled.
Fluttershy blinked. “Wait, that hurt you?”
“What you heard Twilight shout before that was Overdrive,” Celestia explained. “To summarize, it empowers the user immensely, but damages their body proportionately to how much magic they drew on.” She glared at a cringing Twilight. “Then my foolish student went and used Full Expel, which does exactly what the name implies. It funnels all of the user’s remaining magic into the next technique they used. That much raw power running through the body has killed ponies before. It’s nothing short of a miracle that she’s alive.”
Fluttershy’s awe was cut short when she heard a roar come from above. She looked up and her eyes widened at the sight of the Ursa, smoking and damaged, but otherwise okay, hurtling back towards the ground.
Back towards Twilight and the other two ponies with her.
Fluttershy wanted to run, but something inside of her didn’t just resist that idea, it flat out demolished it with an unholy vengeance. Something clicked in her mind, and timed seemed to slow as she began running. She felt something rushing through her body, like adrenaline. Looking up, she saw the bear falling in slow motion. It was angling itself, raising a paw. By the glare it was sending Twilight, Fluttershy correctly assumed it was going to use the momentum of its fall for greater striking force.
Her body was moving faster now. Her wings began whirring with how fast they were flapping. She realized she was flying. Her eyes caught a trashcan lid in the path to Twilight. She scooped it up on her way by. Looking back up, she judged her speed, the speed of the falling Ursa, and her chances.
‘Not enough time to move them. Gotta hope this works.’ she decided firmly. She dived towards her friends and the ponies she had saved. She felt strength flooding her body. As a bonus, she started feeding her Pegasus magic into the trashcan lid, strengthening it. ‘This is gonna hurt…’
And the Ursa came down like a boulder at terminal velocity, slamming its paw into the yellow Pegasus. The force of the strike shook the ground.
Under that paw was the straining form of Fluttershy, using the trashcan lid to stop the paw from hitting the ponies at her hooves. Her face was screwed up as she exerted herself in ways very, very few Pegasi ever managed.
As she did, Fluttershy saw images run through her mind. Bipedal hairless creatures, humans she realized based off of Twilight's description of them. Some were dressed in simple clothes, and worked in a simple town. Some were dressed in greens and browns and looking serious, carrying strange long objects, rifles her mind told her. And some where dressed in important business suits, with cameras flashing in the background as she waved.
The Ursa pulled its paw back and stared at Fluttershy, obviously shocked. Fluttershy panted and groaned. Her body was going to hurt in the morning. The Ursa suddenly roared, and Fluttershy reacted by hurling the trashcan lid like a discus at the bear's face with all of her might. The bear's head snapped back as the trashcan lid bounced back. Fluttershy caught it as she flew towards the Ursa, and struck it in the face with a hard kick that once more made it stagger back.
She remembered being frail and weak. She remembered being bullied relentlessly for her weakness. She remembered life being hard. She thought she would have hid from the world at that point, but the man these memories belonged to didn't give up. Like a certain mare Fluttershy looked up to in her current life, the man, Steve Rogers, fought back. He almost always lost, but he never gave up. He never stopped believing one could succeed if they just tried hard enough.
The bear tried to take a swipe at Fluttershy, but she contorted around the swing, and then once more sent the lid into it's face. It roared in pain and frustration. Fluttershy then flew around its head and bucked it right in the back of the head, sending it staggering forward. She had never felt this strong and fast before. Even now she could feel her body slowly bulking up, gaining strength and speed. Her wings were becoming as strong and efficient as they possibly could, and her mind was getting sharper and sharper.
She remembered joining the Army, wanting to protect and enforce the America way; Truth, Justice, and Liberty for all. She remembered being turned down, and then given the opportunity to become greater than a soldier, to become greater than some piece on the board. If she survived the process, she would become a super-soldier. Captain America.
The bear tried to backhand Fluttershy as it turned towards her, but she deflected it with her makeshift shield. Then she got in its face and reared back, before solidly punching it in the forehead with the shield, using every scrap of strength her enhanced body could call on.
The bear went down like a sack of bricks, out cold. Fluttershy landed a little roughly. She was panting, sore, and all around exhausted... but victorious.
Twilight stared at her friend in shock. "You... you're a Hero Soul?" she asked.
Fluttershy nodded. "I am. I'm the Soul of Justice, Steve Rogers, Captain America."
"I think it goes without saying that the order to suppress medical information on Twilight now extends to Fluttershy," Celestia told Doctor Tender.
The Doctor sighed. "Yes, Your Highness," he said.