The District 17 Switchyard: ordinarily a vital hub for transporting products into Academy City, left almost empty on the still summer evening, with no trains entering and no cargo being unloaded. The only people preventing its total abandonment were a pair of espers, talking before the scheduled start of another experiment.

For but a moment, a third figure appeared, leaving only the strongest Level 5 on his own. Given enough time, he might get bored and go off to do something else, or a replacement for his opponent would arrive from nearby.

It was the curly-haired teleporter that returned instead, adopting an unconcerned posture as she looked across the tracks at Accelerator.

"Only three days? I thought you'd been scared off for good." He would have been right about that, too, if there had been some other option. But being scared for her life was no excuse to let a serial killer continue. Weighing it up against onee-sama's plan… there was no contest. "If you start interrupting like this, it might turn into a shitty crime drama, ya know? Some rich brat gets killed for sticking her nose where it doesn't belong."

That Accelerator was so eager to talk—or maybe the megalomaniac enjoyed the sound of his own voice—was good news. It would give time for Kamijou to catch up and let her test.

"Of course. Even if I wanted to delay the experiments, I would never have taken such an obvious step. The Sisters expect they would need to fight back as part of preparing, if someone were to start abducting them," she answered. It was even why her first attempts to intervene had been so passive.

Hold nothing. Calculate the distance, its 11-dimensional co-ordinates. Make the empty teleportation. Testing in the hospital had told Kuroko that a person couldn't feel anything any more than being teleported to them was a simple instantaneous disorientation. Against Accelerator's passive reflection, the reaching 11-dimensional grasp came back to its origin, the indistinct feeling of remotely touching herself twisted…

The Level 5 didn't even blink. Either that was an astonishing poker face and Accelerator was okay with someone using their powers on him, or he didn't know when something was reflected.

Now, she had to find some way past it.

"The clones? Oh, you took that broken puppet with you! Even like that, it's still a working terminal, right? You used it for information." It was the right conclusion, but the wording made it sound like Kuroko had done something far worse. "But if you don't want to delay the experiments, what the hell are you doing? There're easier ways for you to kill yourself."

Instantaneous and autonomous. From the outside, Accelerator's defence was perfect. Everything the clones had tried to directly harm him bounced off without a second thought. His vision could be obscured, but as soon as anything that wasn't ordinary light or sound hit him, no matter how impossible, it came straight back. They had ideas, the battlefields were prepared accordingly—oxygen starvation, for one—but no direct assault would work.

Then, even while she was still absorbing information, Accelerator had told 10031 what his esper ability really was. Vector Manipulation.

All the garbled reverse teleportation made sense. His automatic defence only reversed all the vectors that made up the teleportation. Orientation, momentum, physical dimensions, gravitational interactions. Whatever was sent got flung back to the right area, but all the non-intuitive correspondences with the object's physical properties were distorted as well. Accelerator had no control over the fine details of how it happened. So, if the reflection reversed into Accelerator…

"I'm stopping the experiments," Kuroko said, as if it was just some annoying paperwork. Still, her body was tense, if Accelerator decided to make a move after this… "I can't save 9969 girls before you murder them. That only leaves stopping them entirely."

Ah, there was the irritated face, if only for a moment, "You already lost once. It's pretty funny, thinking you could defeat the strongest Level 5 after something like that."

Kuroko shrugged, "Of course. I thought I would just ask you to stop, for those girls' sakes. They don't want to die any more than you or I do, but you're the one who can stop this."

Reach out again and again. Count the moments. The delay before she could teleport again was a second, reorienting herself and recalculating everything, but if it were something like her needles, she could queue the slight adjustments one after another with almost no delay. Maybe she could use that, somehow?

"Bullshit!" Accelerator snapped back. That bothered him? "Those puppets keep fighting to the death every time. If they really wanted anything, they would have stopped by now."

Try to follow it up with the inverse teleportation herself immediately? No, that didn't work, it just sent everything spiralling in the opposite direction.

"If you won't stop, then Kuroko will simply have to make you, as many times as it takes." Of course, even if she could argue for coercion, Accelerator's unwillingness might not mean anything. The researchers would hear of his doubt, the Sisters would be forced to deny it. It would only delay the fight. "My duty does not change simply because you're the strongest."

Then… what about a negligible teleportation? Or a movement in place? Accelerator might scramble the vectors, but if the movement components were negligible across the calculation, it would still appear mostly in place. That would be even easier; from Kuroko's perspective it was a teleportation with no change.

"That's real funny. You think you can win even once?"

Faster. Faster. The feeling of grasping for a target ghosting across her skin, twisted reach taking hold of her for a moment. Just chain a little faster, and…

It still "felt" like a body. But not hers. If she could repeat this with some physical teleportation, then…

"Not without doing far more damage than I would like," Kuroko said, confidently. It had been her original plan, but taking the chance to try and end it that quickly before Accelerator could catch on or hit her with something… "But that's why I found assistance."

"You really shouldn't go inviting civilians to other people's experiments, ya know?" Accelerator said, looking over at the backup that had just arrived… panting and out of breath, yes, but the Plan A for ending this without anyone's death.

"Where's Misaka's little sister?"

"How should I know? Your teleporter friend ran off with her before we could start. She might be coming back here, or she could be off to the next site." Hopefully, the answer was neither; Kuroko had taken her all the way back to onee-sama.

"You're doing this every day? Killing them in back alleys every evening."

"Oh, so you saw that?" They must be talking about 10031, then. Why did Accelerator have to look so smug… but she had to hold back until Kamijou was ready. "Blood flow manipulation. It was the first time I'd done it. Not bad, huh?"

"I didn't know humans had so much blood in 'em. Oh, my bad, they're puppets, right?"

"That's enough. Here I was, thinking you were forced to participate in the project. But I guess I was wrong. I'm going to beat you so hard, you won't be able to do it again." With his apparent need to confirm what Kuroko had already told him out of the way, the boy finally broke into a run towards Accelerator.

That was enough to get Accelerator to fight back himself… if what he was doing could really be called "fighting". Just one tap on the ground and a shockwave went racing off towards the onrushing youth, which he had no way to avoid or negate.

This was what Kuroko had been waiting for.

Her preferred option would have been to simply teleport Kamijou up to Accelerator's face, but with that out of the equation, the items placed around the switchyard in preparation would have to do. A few had been brought from outside, but most were liberated from within one container or another—building materials, motor oil, lengths of pipe. Things that wouldn't look too out of place on pallets in such a large transport hub.

In this case, a sheet of some type of fibreboard embedded itself in the shockwave's path. Not enough to block it entirely, but the double boundary prevented it from growing further. And broken pieces of board were much less dangerous than the rock that made up the ground. "Less dangerous" still meaning that Kamijou staggered… but it was better than whatever Kuroko thought a direct hit could have done.

Attempting to corral Accelerator so he could be hit was frustratingly difficult. Teleport a bundle of pipes underfoot? Even if the rolling metal caused him to slip temporarily, the speed with which he could merely touch the inch-thick pipes and send them shooting off towards the both of them made it impossible for the other boy to get in close, forced Kuroko to dodge herself, and gave Accelerator all the time he needed to find his footing.

In fact, the longer it went on, the more the various obstructions and distractions seemed to just be providing new ways to knock Kamijou aside. A sheet of board got turned into a tripping discus, the spilled ball bearings got haphazardly turned into a scatter gun, the motor oil… well, that one Kamijou slipped on himself, while Accelerator got far better grip than was at all reasonable.

It wasn't to say that, even if he taunted them for being too slow, Accelerator wasn't getting annoyed in turn by hopping around like this, not actually landing any particular hit. Whilst Kuroko was strictly limited in her ability to hem him in even slightly by a strict weight limit, Accelerator had no such restriction on the parts of the Switchyard he was able to weaponize in turn.

For the teleporter, it didn't change much that he was now throwing around the very tracks the switchyard ran on or entire shipping containers; if anyone was being too slow, it was undoubtedly the Level 5. The dust the impacts threw up reduced visibility, but as long as her destinations were unpredictable, there was nothing that Accelerator was doing that could hit her. The Level 0, on the other hand…

"This was the best help you could find? I expected someone with an ability, but you just brought a punching bag and kept running away." Accelerator had joined them, then, hopping into this dust-filled dead end made by shipping containers. But while Kamijou was still getting up, it didn't seem like he had gotten through the entire assault unharmed.

"Looks like there's flour in these shipping containers. The weather tonight's nice and calm. This could be a bit dangerous!" How very observant. What, was he going to show how vector manipulation could be used to bake a cake in thin air? No, wait, with dust suspended…

"Have you ever heard of a dust explosion?"

The plus side: she was neither dead nor on fire, and as far as Kuroko could tell, everything was still attached as it should be. Even by teleporting a piece of one of the broken-open shipping containers to them to use as a barrier, that had definitely been a close thing, no matter the warning given to run. On the negative side, things were hurting now, even through whatever damage the electricity earlier had done.

If it came down to it, now she had even less chance to tag Accelerator unless he stood still.

Crawling to her feet, she was glad to see that Kamijou had managed that before her, one of the advantages of not being a slight middle-school girl. Even better, while the taunting Level 5 had shrugged off his own explosion without apparent harm, he was finally doing the very thing that Kuroko had been trying to manoeuvre him into from the beginning: getting within arms' reach of her assistance.

It was immensely satisfying to watch Accelerator get punched in the face after everything that had happened. Particularly when it happened again, and again, the Level 5 abandoning all pretext of trying to use his abilities intelligently in favour of flailing around ineptly against someone that, from what Kuroko could see, was at least highly used to brawling.

Then things got worse, as even after being laid out on the floor—and lectured again on the Sisters being living people, not guinea pigs for him to slaughter—Accelerator seemed to hit on the idea of creating a tornado out of nowhere. With Kamijou being immune to teleportation too, there was nothing Kuroko could do except hope that when he came down he would still be alive and retreat to a safer distance.

… which apparently meant running into onee-sama and 10032.

"What are you doing here!?" Not, apparently, that this was the time to ask—from the impact of Kamijou and the unfortunately-placed wind turbine, all of them had more important concerns. Then… "Check on him."

She teleported once more—even with the distraction the pain was starting to provide, it felt far more achievably than climbing the chain-link fence would have—into Accelerator's blind spot. What he was doing—compressing the air for miles around, controlling enough wind to affect all of Academy City or more—had to be taking a lot more focus than his unconscious reflection, or any of the attacks he had been flinging around. If his attention could be broken, it would stop.

Kuroko fanned needles in both hands.

She could do this. It wasn't conceptually different from mindlessly teleporting her pillow back in the dorm; just send the needles, don't let go, and immediately teleport them again. The target was stationary and unaware. If she didn't do this, onee-sama and Kamijou and 10032 were all going to get caught.

One by one, the needles disappeared from her fingers. And with a scream of rage and pain, Accelerator's control over the winds of Academy City was broken.

"What the fuck did you do!?" the Level 5 snarled, turning around, arms lowered with difficulty—and even that was a terrible idea, only aggravating the warped needles pockmarked through his upper arms, from elbow to shoulder. Retrieving that mess from the joints was hard enough as it is, and if he wasn't careful, he would definitely tear something.

"Use the knowledge of ten thousand battles against you." Although not perfectly—not all the needles were in Accelerator. It was definitely better she had avoided anything incapacitating… even if she had no way to end this fight herself. "I told you the Sisters wanted to live: this was their help. The experiment ends here."

"Ends here? You think just because you got a few pinpricks in, this means you beat me? You're just a cocky Level 4 that got a lucky hit! But you're annoyin' me now, so I'll just kill you, then the doll. Like hell you'll stop the experiment."

The sound of feet bracing against the switchyard rock drew both their eyes. Despite the shock, the near misses from all the switchyard items, the explosion, and even being thrown through the air like a ragdoll, Kamijou Touma had managed to stand up once again, prying himself free of onee-sama and the Sister.

Accelerator couldn't seem to decide which of them he wanted to go for first. The seconds-long pause was more than enough time to simplify the answer for him despite the needles in Kuroko's hands, unsteadily appearing on her feet behind the spiky-haired boy. If this let her lean on onee-sama for support… well, that was a happy coincidence.

For someone so unfamiliar with pain or being hurt, Accelerator had to be given credit for stubbornness—even if reaching out his arms in this condition was still an idiotic move. Maybe that was why he failed so completely. Maybe he hesitated, for some reason Kuroko couldn't tell. But this time, as Kamijou punched him in the face with another cheesy one-liner, he didn't get up.

Accelerator had lost, to a girl he drove off twice and a Level 0. No matter what way you looked at it, the plan didn't cover this. It shouldn't be possible.

The Level 6 Shift project was over.

AN: Letting people prod away at your automatic defence all the time? Not so good. Although, it's not his fault that it could be done invisibly.

Between Touma being marginally less beaten up and 10032... not at all, a certain someone hasn't gotten to actually confirm they're her sisters. I'm sure they're not going to have issues with that at all.

That leaves the wrap-up for the Sisters Arc. Then probably some railgun Slice of Life before Three Stories?