My Hero Automata

Summary: What's a little risk of tearing reality apart when you really need a big boom?

Warning! Chapters 78-80 were all published back-to-back! Make sure you don't miss any of them!

Chapter 79: Risky Business

The island of Gajajima had been inhabited, once upon a time. It had, however, been abandoned even before Quirks became a thing. The 3km long and 2km wide chunk of rock had been hammered by a series of typhoons, clear back in the latter half of the 1950s, then had its local fishing industry collapse just for good measure. The advent of Quirks hadn't really changed anything for the island. Oh, certainly it was exactly the sort of place that might attract some villain setting up shop. It would have been even more attractive to all sorts of smugglers, given its position in the Easy China Sea to the south of Japan's main islands. The trouble, of course, was that the Coast Guard and JSDF were aware of that fact, and the island was checked on fairly frequently by patrols.

All of which meant that it was perfect for what they needed at the moment. The closest inhabited island was Yakushima, and even it was far enough off not to be at much of a risk from their experiments. Meanwhile, the centuries-old, abandoned ruins of a power plant, school, admin center, and small town all needed enough of an eyes-on-check that the JSDF had a solid map of where they could set down and set up. There was, of course, no way in hell that Izumi was going to let anyone be on the island when they ultimately tested the crude abomination they were creating. But dropping a few crude military pre-fabs and pulling her equipment out of her digital inventory gave them a quick-and-dirty basecamp-cum-lab to work out of while building said abominations, at least.

With willing hands from the JSDF, plus Momo and Izumi, the whole crude lab was up in a few hours…and Izumi and 2B had spent virtually every second since the early-morning conversation modeling possible options. A disgruntled-but-willing Bakugo had been put to work the whole time, mostly as a way to make him sweat, with that sweat being collected for use in the shaped explosives Izumi needed to make. Few people realized that the reason Katsuki's sweat was compared to nitroglycerin had everything to do with how powerful it was. He didn't sweat actual nitroglycerin, of course. Doing so would have likely resulted in a lot of dead people around him, either from shock-explosives or from its nature as a contact vasodilator.

Instead, in a display of the usual bullshit-effectively-magic that Quirks were, the bio-chemical he actually did produce was both a little bit more potent than nitroglycerin, and far more stable. In fact, it was far more stable per milliliter than any conventional high explosive of similar yield. The only way to trigger it, aside from Katsuki's own Quirk, was rapid high-temperature shock. Something replicated in the gauntlets he used for more powerful, focused blasts, via a sparker that used magnesium to deliver that heat under controlled conditions.

All of which was exactly why Izumi had requested him. They needed something powerful enough to destroy one of their storage crystals, which were made tough in the first place. That something needed to be heavily infused with QE so that the explosive properties affected the QE field rather than just the crystal. Which, given its degree of bullshit, was very true of Bakugo's sweat. And lastly, it needed to be something that they could manually trigger, with nothing but mechanical or chemical means. All, of course, while being malleable enough to rig into a shaped explosive.

It would have taken weeks to produce something equivalent artificially. Possibly months. Thankfully, they had a natural source, even if said natural source was irked about being pulled from the front lines to be little more than manual labor. To his credit, Katsuki had kept the grumbling and gritted teeth to a minimum, fully understanding just how important this could be to the overall effort to save humanity. The fact that he knew both Momo and Izumi hated being pulled from helping themselves likely also helped with his temper. Despite that, there was impatience in his voice as his tolerance finally ran out.

"How much fucking longer do I need to be here?"

Izumi didn't bother to answer him, deep in hypercongnition mode, working with 2B on modeling outcomes. Momo fielded the question easily in her place.

"That's going to depend on the numbers of trials we need. From what I can see, Izumi and 2B almost have the first model set done. We're working nearly blind on what the effects of this are going to be, so we're going to need to try incrementing damage and various models. The last thing we want to do is open a Rift ourselves. Particularly as we don't know how they work. We could as easily open one into some sort of eldritch abomination instead of the invader's world, if we get unlucky enough."

Katsuki looked a little leery at that.

"Aren't you two basically the foremost experts on Quirk Energy Fields in the world? You really don't know what this will do?"

Momo shrugged and shook her head.

"No. To give you a frame of reference, we know for sure that high enough concentrations of QE will start a disease-based chain reaction in carbon-based lifeforms that literally turn said lifeforms into salt. There's some evidence that the disease is actually a form of extradimensional link to something that causes active mutation. Something only made more likely by the way we've seen so many monsters with mutations since the Gate opened. Humans managed to adapt to naturally produce the stuff, and our own QE isn't harmful to ourselves. But you can actually still cause some pretty horrible, and horribly lethal, cell mutations by infusing someone else's QE into another Quirked individual."

Bakugo was far from an idiot. He was, in fact, near the top of their class. Only outshone by ridiculous outliers like Momo and Izumi. As a result, his brow furrowed and he almost immediately made several of the same connections Izumi had on the first day of the invasion.

"That's why the monsters are mutated. The enemy, they aren't just harvesting QE for the Rifts and Gates. They use it to fuel their war machine in the first place. They figured out how to guide the mutations into creating specific effects in specific creatures?"

Momo nodded grimly.

"That's the current theory, at least. We also think their own world has a lower QE level, enough so that they have to collect a lot of it slowly, then focus it via various means in order to create effects our Quirks do naturally. In which case, access to far greater amounts of QE might be their entire purpose in invading. Every Quirked human is essentially a QE battery for them to harvest. While the planet itself has more QE as well, due to the ambient QE everyone sheds every day."

Bakugo's face turned grim and haunted, putting together pieces that clearly hadn't occurred to him yet. Understandably so. He'd been fighting on the front since the start, doing little more than fighting, eating, and sleeping, like so many of those with powerful combat Quirks. This was likely the first time he had enough information to consider the why.

"Fuck. If we're literally just fuel for them…fuck, that's messed up." He shook himself and waved at the handful of QE Storage Crystal present in the crude lab. "And you think giving them more QE will…no, wait. The mutation thing, right?"

Momo nodded, seeing he'd gotten to the same mental place as one of the options of what could happen, at least.

"One possible outcome is that the QE burst will cause runaway mutations in all of their monsters. Or instabilities in those parts of them already mutated. Combined with the fact it might actively disrupt the QE fields of their world enough to cause them issues opening more Rifts…"

Bakugo nodded, but there was a frown on his face too.

"Even if both things happen, these invaders clearly know as much or more about QE as you do. They'll eventually absorb what you set off and use it. In the long run, this might just give them more fuel."

Momo shrugged.

"It's almost certain it will, actually. Unless the disruption is far worse than we believe. But what we need right now is breathing room. If we can even just temporarily slow them down so that we can get on top of the defense…"

Bakugo nodded again, taking a deep breath a moment later. The irritation was gone when he spoke again.

"Alright. Then I'd better get back to making myself sweat. If this works at all, we'll need a lot more."

With that comment, he left the lab area, and Momo went back to checking on Izumi's progress…

... ...

There were a lot of eyes watching Izumi as she stood on the flat-top of the helicopter-carrier JMSDF Koga the third day after she'd been asked to whip up a miracle or two. The fact that the Koga had been diverted for this, pulled away from launching its helicopters in support of anti-monster duty against particularly remote Gates that formed on the smaller islands of Japan, said entirely too much about the danger of what they were doing here. Izumi had almost no idea what was going to happen, even as she sat in front of the console that controlled the remote detonation of their test rigs. The need to get speedy results had meant Izumi didn't do a single model, test, then remodel. She'd made a full dozen different models of their potential weapon, had them all charged, and scattered them as far from each other as possible on the small island. Hopefully, a successful test wouldn't set off the others. But they couldn't be at all sure about that.

They honestly couldn't be sure of much, actually. Izumi herself was only sure that she now fully understood what Oppenheimer and his team had felt like during the first tests of the Manhattan Project. Back when they had been seriously, seriously unsure what they were about to unleash. They hadn't even known if what they were about to do might literally ignite the Earth's atmosphere or crack the Earth's crust. They'd only been somewhat sure that wouldn't happen. Just as Izumi was currently only somewhat sure that she wasn't about to cause a repeat of the Shinjuku Event from 2B's original dimension.

She didn't think the MASO energy about to be released here was nearly large enough to cause that sort of incident. But she couldn't be truly positive she wasn't about to cause a chain reaction of some sort. Worse, YoRHa had only possessed extremely fragmentary information on the two entities that caused that event. The origins of the Giant and the Dragon were utterly unknown, but presumed to be extra-dimensional. Meaning Izumi also didn't know if she was opening a Rift into some place filled with more monsters like those. Perhaps worst of all, she couldn't even share that fear properly. There were, after all, exactly five people alive that knew 2B's entire story. Herself, 2B, Momo, her mother, and 2B's therapist. That was it. The total extent of those aware of 2B's true history, and the only ones she could possibly have confided her full fears in. She'd done so with 2B and Momo, of course. But that made for only three people in the world that knew how dangerous this might actually be.

Well, at least she'd pointed out the idea of Lovecraftian Horrors being possible, and the military were sufficiently paranoid about 'alien bullshit' right now that that they'd sent the carrier. A carrier fully loaded with attack helicopters that were ready to reduce the entire island to an afterthought if this went wrong enough.

It would have to be enough.

With one last bracing breath, Izumi raised her voice.

"Test 1, commencing. In 5, 4, 3, 2, 1…detonation!"

There was a flash of violence from the island…but then nothing else. All of those on deck tensed, waiting, waiting, and waiting more…until Momo finally spoke up from where she was monitoring.

"Negative Effect! Crystal is intact!"

There was a sigh, a releasing of tension, but Izumi was grimly determined and moved on.

"Test 2, commencing. In 5, 4, 3, 2, 1…detonation!"

Another flash of fire and flame, this time accompanied by a spike from the QE monitors. A long, slow wait of five minutes, then Momo spoke again.

"Negative Effect! Crystal cracked and seeped QE, but not fast enough. Activating siphons to counter the QE rise."

There was a much longer wait, almost half an hour this time, during which everyone first relaxed, then re-tensed as the QE levels returned to the baseline they'd established for the tests. A deliberately somewhat low baseline, on the assumption that the invader's world had a lower ambient average QE level. Finally, Izumi triggered the warning lights again, waiting for the signal that the attack crews in the choppers were once more ready, and proceeded.

"Test 3, commencing. In 5, 4, 3, 2, 1…detonation!"

This time, there was an immediate difference from the previous destinations. There was only a brief flash of light before that light seemed to reverse in on itself, like some greater power had reached into the universe and pressed 'rewind' on light itself. Halfway through that reversal, the light went chaotic, looking like someone had smashed ten thousand kaleidoscopes in the middle of a rave. The QE monitors went, for lack of a better descriptor, psycho. They wobbled and spiked erratically…then exploded into visible sound.

Not sound waves. Visible sound. For just a moment, as the hypersensitive instruments overloaded with chaotic QE, everyone looking at them suddenly had a haunting understanding of what the sound of chaos looked like. Screams and retching was the reaction of many, with a few even collapsing into seizures as their mind failed to process. And then it was gone and there was panic on the deck as everyone tried to help those who had collapsed…and tried to figure out what in all that was holy and a few things that weren't, that had been…