The sound of sneakers smacking against concrete echoed off the walls, audible over the thunderous drumbeat of her heart and her ragged gasps as she sucked in air. Mikoto could feel her pursuers getting closer as she rounded a bend in the concrete hallway, taking cover behind a stack of metal crates covered with yellow warning labels, hoping to get a moment to catch her breath. She winced as she knelt down, trying to avoid putting too much pressure on her left leg. Blood leaked from a deep gash in her thigh, dripping onto the floor as she flattened herself against the crates, her eyes narrowed in concentration. She just hoped her pursuers didn't notice the trail of blood she had left in her wake. A moment passed and she heard shouting down the corridor. Clearly that had been a bit too much to ask.

"Tch..." Mikoto took off again, doing her best to ignore the pain in her leg. Even she wasn't used to exerting herself to this degree for so long, but she had no one but herself to blame for that; she had tried to finish the fight quickly, without first understanding her opponents or their abilities. She'd taken several hits before she was even aware her attacks had failed, and now she was in dire straits. Her head was swimming, and she was starting to lose focus. Hopefully it was from overuse of her ability, rather than blood loss. She didn't relish the thought of passing out at a time like this.

If a clone of yourself suddenly appeared in front of you... what would you do?

The air around her shimmered, and Mikoto bit off a curse as she twisted on her good foot just in time to avoid a blast of pressurized air. It slammed into the wall behind her with an ear-splitting shriek, gauging a large chunk out of the concrete. Mikoto turned just in time to see a girl at the opposite end of the corridor raising her hand, palm forward, before the air began to vibrate once again. She dropped to the floor, a bolt of electricity arcing from her bangs with a violent crack to strike the girl in the chest just as she was joined by a boy a few years her senior. The girl screamed before collapsing to the floor, twitching. Mikoto winced at the sound, but didn't have any time to feel sorry for the girl before her companion let out a cry and launched a wave of flame across the floor.

The flames flowed like a blazing river, washing over her hands and feet before she could get out of the way. She screamed, the flames turning her skin an angry red and the pain clouding her thoughts as she scrambled back to her feet. This was getting bad. She blinked back tears, trying to put some distance between herself and the pyrokinetic. Hadn't she already taken him out? She had a very clear recollection of hitting him square in the back with a bolt of lighting. Maybe she hadn't hit him as hard as she thought, or one of the other espers with him had some kind of healing ability. Either way, she needed to finish him quickly, or she was in trouble. A prolonged fight in her current state wasn't something she was going to win.

I suppose... it would creep me out. I'd probably want it to disappear.

Sweat poured off of her as she darted down another corridor. She was nearly running on empty, but she couldn't stop now. The pyrokinetic was closing in, his heavy steps echoing off the walls. Just as she reached the end of the passage, the floor beneath her bucked and heaved, the concrete cracking and throwing her off her feet. Mikoto landed on her hands with a grimace, the burnt skin of her hands bleeding as it cracked and peeled.

The air was rent by a deafening crack as a fissure opened in the ground, racing towards her. A brief burst of magnetism pulled her up to the network of pipes above her just before the floor split apart and crumbled. Mikoto cast her senses about, trying to locate the esper responsible. Things were getting out of hand; she had assumed the pyrokinetic was the last one left, but it looked like there was an earth-based esper still lingering about somewhere. He must have kept his distance during the earlier confrontation, probably waiting for a good moment to strike. Mikoto struggled to recall what she knew about terrakinetics. All she could remember was that their power was greater the closer they were to the earth they were manipulating. For him to be able to do this much damage without even being able to see her, he had to be at least mid level four.

Misaka has a manufactured body and a borrowed soul. Misaka is nothing but a lab rat that costs 180,000 yen.

The pyrokinetic rounded the corner and hurled a blast of fire at her head, forcing her to drop back to the ground. Flames blazed past her, and the acrid smell of burning hair filled her nostrils like poison. She twisted her body as she hit the shattered ground, narrowly avoiding another fireball. Pain tore through her back and she hissed as her skin erupted in angry blisters. The air around her began to heat up as the man prepared another attack. She launched several bolts of electricity at him, forcing him to fall back as he tried to avoid the strikes. Mikoto cursed as several of the flashes lanced past him. It was getting hard to control the current as the temperature increased, and she was already exhausted.

She leapt over another wave of flame, sprinting over the ruined floor towards her target. He stumbled back in surprise at the sudden aggressive tactic. Mikoto launched herself forward with a sudden burst of speed, burying her shoulder in his gut and sending them both tumbling to the ground. The heat around them began to dissipate as the flame user rolled on the floor, gasping for air. Mikoto rose painfully to her feet, preparing to launch an electric volley to incapacitate the man, when the ground once again shifted beneath her feet, separating her from her target. She stumbled, nearly falling again. By the time she had regained her footing, the man was on his feet again, brandishing white-hot flames in his hands as the rumble and cracking of stone filled the air.

"Damn, you're a lot tougher than you look," the man said, breathing heavily. "Guess I shouldn't be surprised. Looks like level five isn't just a fancy title."

Before Mikoto could respond, the fire in his hands stretched and twisted, reaching towards her and cracking at the air like whips. She hopped back, ducking and weaving to avoid the flames. The corridor made it difficult to get a good angle on her opponent, and the intensity of the flames distorted the air, making it hard to tell exactly where he was. The level of control he had was impressive as well; the flames raked across the floors and ceiling as he pushed her back, leaving scorch marks in their wake, but never dissipating. Mikoto briefly recalled the level three pyrokinetic Kuroko had tangled with during her first meeting with Uiharu and Saten. Compared to this guy, he had been nothing but a kid playing with matches.

Would you be willing to provide us with a map of your DNA?

Mikoto ducked and dodged, steadily losing ground as she looked for an opening. 'Dammit,' she thought, narrowly avoiding another lash, 'this guy really knows what he's doing. I'm too worn out to overpower his flames, and he's not leaving himself open at all. I need to come up with something else or I'm toast.'

The ground beneath her feet shifted again, and she threw herself backwards to avoid the eruption of stone. She nearly collided with another crate. An idea quickly formed in her mind and she grinned, hopping over the crate and ducking down behind it as another blast of flame passed overhead.

In an instant, Mikoto magnetized the crate, and with a flick of her wrist sent it hurtling down the corridor towards her opponent. The flames cut off and she heard his muffled curses as the heavy crate collided with his gut, sending him crashing to the ground. She was up and charging as he hit the ground, and was upon him before he could get his bearings back. His eyes widened in shock and fear as she barreled down on him. He threw up his hands in a panic, sending flames lashing out at her, but it was too late. Mikoto unleashed a static charge point-blank, sending the pyrokinetic into seizures before he fell unconscious.

In the end... this loser was born to be killed by me.

Mikoto rose slowly, nursing her scorched hands and arms. His last attacks may have been desperate, but she hadn't been in much condition to fend them off. The results were a few more burns and a great deal of pain. She let out a few ragged breaths, trying to steady herself and stop her hands from shaking. The floor rumbled again, and she let grit her teeth, taking off down the unbroken hall. Looked like now wasn't the time to be licking her wounds.

"One more," she panted, reaching out with her power, trying to feel his presence, "Just need to find a way to nail him down."

The whole complex seemed to be shaking, but Mikoto paused, taking a moment to calm herself. She needed to focus if she was going to find him—racing around blindly wasn't going to get her anywhere. After a moment she was able to calm her breathing, reaching as far as she could with her ability. The ground shifted beneath her and she jumped to get out of the way of the breaking concrete, letting out a frustrated growl. The esper was clearly skilled, and on top of that, he appeared to be able to sense where she was as long as she was touching the ground. She needed time to be able to find him, and he didn't seem like he was going to give her the opportunity to focus. The tactic might have been admirable if it wasn't so damned annoying.

Even in the best of circumstances, using the electromagnetic waves that her body emitted to track someone in a structure made mostly of concrete was tricky, and exhausted as she was it was nearly impossible. Mikoto let out an aggravated cry, diving out of the way as a section of the wall collapsed where she had been standing. At this rate he'd be able to corner her, and she didn't have enough strength left to save herself if he decided to bring the corridor down on top of her. She needed a plan, and fast.

Those girls too, lived their lives as best they could.

A rumbling filled the corridor, and cracks began to appear in the floor and walls. It felt like the whole facility was shifting beneath her feet. Mikoto took off as fast as her injured legs would let her. It looked like the terrakinetic had decided now was a good time to try to finish her. She was out of time; she needed to do something now.

A chunk of concrete fell from the ceiling, grazing her shoulder and sending her crashing to the floor. Mikoto stumbled back to her feet as the ground beneath her heaved, breaking apart as if trying to swallow her whole. She ducked down another corridor as the floor gave way and hugged the wall, gasping desperately for breath. Her whole body was shaking from exertion, and the world went dark as she wobbled, barely able to keep herself standing.

"This is so stupid!" she growled. "How am I even supposed to find this guy if I have to keep running away? I need a way to extend my range, but this damned building is made out of concrete!"

Mikoto wracked her brain for anything that might work, but she was having a hard time focusing. The pain from her cuts and burns was starting catch up with her, the adrenaline coursing through her veins no longer enough to hold it at bay. Her whole body was covered in a mixture of sweat and soot; her hair clung to her neck and face, and sweat was dripping into her eyes, obscuring her vision. She started as something cool dripped on her from above, the liquid soothing the burns on her neck, and she paused, looking up.

The pipes! Mikoto mentally berated herself for not thinking of it sooner. The pipes ran through the entire complex, running along the ceiling. Putting her weight on her uninjured leg, she leapt from the ground, using magnetism to pull herself up to the pipes. As soon as her hand made contact with the cool metal, she sent a burst of electricity through it. Even if she couldn't use the electromagnetic waves given off by her own body to find the esper, once she knew where he was, tracking him wouldn't be an issue. Espers each gave of a distinctive signal that was simple enough for her to recognize once she had felt it once, perhaps a side effect of their unique AIM fields.

The electric signal returned to her almost instantly, and her face twisted in a feral grin. "Found you!"

I know we're both level fives, but... I had no idea your best move would be so pathetic.

He wasn't far, a few hallways down and on the other side of the wall. Mikoto took off, hoping to get to him before he realized she'd figured out his location. Now that she knew where to look, pinpointing his location was easy.

Unfortunately, it seemed he was paying more attention to her movements than she had hoped. As soon as she was close to striking distance, he took off, putting more distance between them. Under ideal conditions, Mikoto was almost certain she would have been able to run him down. As it was though, he was able to easily outpace her. After a few minutes of chasing, Mikoto stopped, gasping for air and doing her best not to fall to her knees as she struggled to catch her breath.

'Dammit!' she thought, tracking him as he stopped. The ground beneath her feet started to shake again and she staggered forward. 'If we can both tell where the other one is, but he can attack me outside line of sight, how am I supposed to beat him? I can't even catch up when he's moving!'

Mikoto took off once more and the terrakinetic followed suit. The instant he started moving, the ground stopped shaking. It looked like he could only use his ability against her when he wasn't moving, although he could clearly still tell where she was while he was running. Maybe using his ability on something he couldn't see took a great deal of concentration? Her leg gave out as she was considering this possibility, and Mikoto crashed painfully to the floor. Her opponent once again ceased his movement, and the ground trembled.

"Looks like I'm out of options," Mikoto grumbled, clambering back to her feet and reaching into her pocket, feeling for the familiar metal of her coins "I just hope I've got enough left in me for this."

You've seen plenty of this city's true face. The inhuman actions carried out to create a level six. The human experiments using child errors. The use of a negotiator to trick you out of your DNA map.

Electricity arced across her arm as she raised her hand towards the wall, ignoring the ground cracking beneath her. He was straight ahead, three hallways down, about twenty meters. With one last burst of energy, she flicked the coin. There was a deafening roar and an explosion of blue and orange light filled her vision as she was thrown back against the opposite wall with a dull crunch. She'd never fired a railgun point blank before. Her vision went dark for a moment and all she could hear was an intense ringing in her ears. In a daze, Mikoto couldn't help but think the blast had killed her.

When the ringing finally stopped and she regained her sight, she realized the floor was no longer shaking. She picked herself up off the ground, gasping in pain. Her shorts were torn, and her shirt hung off her frame in rags. Dust and debris filled the air, obscuring her vision and forcing her to cover her mouth with what was left of her shirt. It was several moments before the dust settled and she could make out the aftermath of her reckless attack.

There was a massive hole in the wall where her railgun had impacted, and the destruction continued through several more walls, casting plaster and concrete in its wake and carving a deep groove in the floor. Twisted rebar and sparking wires jutted from the wall where her coin had torn through the solid material, and Mikoto was seized by a brief moment of panic. The fact that she was no longer under attack meant her opponent had most likely been rendered incapable of using his ability. That meant he was either unconscious, severely injured, or...

"I think that will be enough for today, Misaka-san," a calm voice spoke from a speaker overhead.

Mikoto grimaced, the voice sending shivers down her spine. She turned and glared at a wall-mounted camera, watching with some satisfaction as it sparked and fizzled, smoke curling up from the ruined equipment. These experiments were tasteless enough without the added discomfort of being watched like a rat in a maze.

"I suppose next time we'll have to use some more durable insulation for the cameras," the voice spoke again. "It looks like the interference from your railgun was too much for them. It's remarkable any of the equipment in this place is still working, really, with the way you've been tearing around. I must say, I'm impressed, Misaka-san."

Mikoto couldn't suppress the shiver that passed through her body every time that voice spoke her name. It was cold and calculating, but at the same time always sounded as though it was observing something deeply amusing. It made her sick to her stomach just listening to the man.

"That terrakinetic," Mikoto asked between breaths. "Is he okay?"

While it's true she has a kiddie taste that isn't suitable to her age, and...

"Hm? Oh, yes. I imagine he'll be fine after a week or so in the hospital, though I imagine he'll walk with a limp for a while. Still, the damage is minimal compared to what it would have been had he taken the blast directly. I daresay there wouldn't be anything left of him if he had. You have impeccable aim, Misaka-san. To think you'd be able to fire a railgun shot at an opponent you couldn't even see and still miss him intentionally. Most impressive, Misaka-san. Quite well done."

She's crude,

Mikoto clenched her teeth, biting back the angry retort that bubbled to the surface. She hated these researchers. All they were interested in was advancing their studies, in finding the next step in the evolution of espers. They didn't give a damn about who got hurt in the process, as long as they got some promising results. But as much as she hated to admit it, she needed them right now. There was only so much she could do with the standard curriculum, and working on her own could only end in disaster. For now, she needed to play along. Just one more lab rat.

Short tempered,

"So are we done here, then?" She panted, trying not to sound as though she were about to keel over. "I still have some homework to do."

Quick to pick fights,

A chuckle sounded from the the speakers. "My, my, such a dedicated student you are, Misaka-san. It's no wonder you are the pride of Tokiwadai. Yes, I think that will be enough for today. You've given us quite the impressive display today; I can't wait to review your performance. In the meantime, why don't you come back up to the labs and we'll get you patched up. You took quite the beating there, after all."

And on top of that, someone who won't admit she likes what she likes,

Mikoto merely grunted, staggering towards the exit to the underground complex that had served as her arena. She just hoped none of her injuries would leave too much of a mark; she didn't relish the thought of having to explain herself to Kuroko.

She's a troublesome big sister that would even throw her life away for Misaka.

"Really, Misaka-san, you push yourself too hard during these tests. You won't be doing anyone any good if you keel over in the street."

Mikoto winced as the doctor attending to her, a young woman with long, blond hair done up in a bun and a quiet, playful voice applied antiseptic to the burns on her back. "Hehe, guess I've never been that good at doing things halfwa—gah! That stings!" she hissed, the foul-smelling liquid stinging her wounds.

"I told you to hold still, Misaka-san," the doctor said with a sigh. "I don't understand you espers at all. What's the point in having all that power if all it does is get you hurt? When I was in school, the worst we had to deal with was getting our hair pulled and being called rude names. I guess when you introduce supernatural powers to a bunch of children things are bound to go bad."

"I'm not a little kid," Mikoto fumed, trying to ignore the stinging pain as the doctor wrapped her back and chest in gauze. Like everything else, Academy City had put a lot of time and money into advancing the field of medicine. The material most bandages in the city was made out of was not cloth, but rather an elastic material laced with proteins designed for the specific purpose of clotting blood and stitching together wounded flesh. Soon, the pain was replaced by a numbness and an almost pleasant tingling sensation.

"Hm, sorry. I'm almost twice your age, so it's hard for me to see you as anything else, especially when you pout so adorably like that."

"S-shut up," Mikoto spluttered, he face turning red. "I'm still a level five you know! Don't treat me like some little princess!"

"Ah, yes! Like that! So cute!" The woman said, clasping her hands together and squealing in delight.

"R-really," Mikoto huffed, calming down and trying to fight back the blush that had spread through her cheeks, "And you call yourself an adult."

"Well, sometimes even us adults need to have a little fun at the expense of our juniors," the doctor said, chuckling as Mikoto stammered.

They continued in silence, Mikoto too flustered to speak coherently and the doctor too amused to change the topic, until all of Mikoto's wounds had been dressed. She was still exhausted, but the pain had been numbed to some degree, and she found she could stand without falling over. Still, these sessions were taking too much out of her. She wasn't progressing fast enough.

"The burns on your hands and arms are minor," the woman said, back to business. "You should be able to remove those bandages in the morning, so long as you keep them on while you sleep. The covering on your back you'll need to keep on for a while longer, maybe a week. The blistering was pretty bad, so if you don't want it to scar you'll need to keep that bandage on. I stitched up the cut on your leg, but keep that covered too. Other than that you'll have some bruising and a few minor cuts and scrapes. The burns are the worst of it though, so just keep an eye on it and come back immediately if something doesn't feel right."

Mikoto stood, trying to keep as much weight off her leg as possible. The pain wasn't nearly as bad as it had been, but she still felt weak, and her leg shook when she tried to put her weight on it.

"Careful on that," the doctor said, nodding at Mikoto's injured leg. "The painkillers will take care of the pain for the most part, but you should still keep from doing anything too strenuous while it's healing. That cut came close to doing some real damage, so it would be best if you didn't aggravate it. Try not to walk too much if you can help it."

"I get it," Mikoto grumbled. "You don't have to treat me like a kid."

The doctor merely shrugged, smiling at her. "Well, far be it from me to tell the mighty Railgun how to take care of herself. Still, taking on seven level fours at once is no mean feat, even for you, miss third-ranked esper. Besides, as long as you're doing these tests, I'm your doctor. It's my job to be worried about you."

Mikoto felt her cheeks heating up and scoffed, turning away from the woman. "W-whatever. As long as I can keep improving my ability I can handle a little pain. A few scrapes aren't going to keep me down."

"Such an admirable spirit," the doctor said with a wistful sigh. "I wonder if it's just part of being young?"

"Don't be ridiculous."

"Well, maybe not. Anyway, take care of yourself, Misaka-san. We'll see you again in a few days, then?"

"Yeah," Mikoto said, pulling her Tokiwadai vest on. The clothes she had worn during the experiment had been incinerated as soon as the test was concluded. This had been a condition Mikoto had set after the first test, when it became apparent that she wasn't likely to escape injury during these exercises. She wasn't foolish enough to believe that if the scientists wanted to, they wouldn't be able to secure a sample of her DNA in some other way, but it still made her feel better. After what had happened the last time Academy City's researchers had gotten ahold of her genetic code, she wasn't prepared to take any chances in handing it out to someone else.

"Let me know when those other espers recover, alright?" she asked.

"Of course," the woman said, offering her a kind smile. "I'll notify you as soon as they are fully recovered. I promise to take good care of them."

Mikoto let out a sigh, feeling some of the tension leave her shoulders. "Good, thanks. I... I appreciate it"

"Don't worry too much about it. They all volunteered for this, after all. It's not like you're being a bully. They wanted to test themselves, and saw this as an opportunity to push their limits. They knew the risks involved in challenging a level five. Worrying too much about them is an insult to their determination to improve themselves."

Mikoto simply nodded. After the first test, she had seriously considered calling the experiments off. As much as she wanted, no, needed, to get stronger, she never wanted to hurt anyone in the process. Hospitalizing five espers for a week hadn't been what she thought she was signing up for when she approached the managers of this facility with her offer. But she couldn't think of any other way, and as much as she hated hurting them, she couldn't stop now. She had a responsibility, and she would be damned if she turned her back on that now. This was a problem she had created herself; she had no right to walk away from it.

"Yeah, I know," Mikoto sighed, pushing her stray bangs behind her ear. "You're right. Anyway, see you next time."

The doctor watched Mikoto as she left, walking with a noticeable limp. It was such a shame to see someone so young pushing themselves so hard, but she understood what Misaka was feeling; the pressure of guilt and responsibility that must have been crushing the young woman was a feeling she knew all too well. There was a time when she would have thought it unthinkable for someone so young to be bearing such a heavy burden. Those days were long past. Now, all she could do was help when they came to her, battered and broken. If a kind word and a smile was what it took to keep them going, then she was more than happy to oblige. It was the least she could do after what she had done.

"I wonder sometimes if we all wouldn't be better off if this city had never existed," she whispered, before turning back to her desk and beginning the arduous process of reviewing the results of Misaka Mikoto's latest experiment.

A/N: So despite the fact that I really didn't like the idea of having more than one story going at the same time, I started this one. That tends to happen when I get obsessed with a character though, and Mikoto has made it into my list of favorite characters from anything. As far as canon goes, I'm going off of what has been released so far in the Railgun manga, so this would take place sometime after the Daihaisesai arc. I haven't read the light novels, so I'm sure I'm going to screw some things up related to that, but I'm not too concerned. Consider it an AU if you like. The Railgun manga has enough differences from the Index story line that I'm not going to tear my hair out trying to get them to mesh. I don't anticipate getting yelled at anyway, it doesn't seem like there are a lot of people reading Railgun/Index fics. I'll be happy with just about any response, but if you read it, please do let me know what you think. Thanks!