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Catastrophe Theory

A Bleach Fanfic

Chaos Theory AU

Chapter Two: Trouble on the Way

When the Senkaimon opened, it spat her out in her childhood.

The whole thing was pretty surreal—over time, her memories of her years in the living world had faded until she kept only the really basic stuff. Her family, a few pieces from school, some random information about how humans lived. But seeing it again right there brought those things to the front of her mind—a place they hadn't been in a long time. She saw a car and knew what it was, even if there weren't any such things in Soul Society and she'd forgotten about them before.

It had been the same way as when she came here to help Urahara; there hadn't been much time then, though. This was different—Renji said there was no way of knowing just how long they'd be here. War wasn't usually waged all at once; it happened in stages, with big gaps of waiting in between them.

"Kurosaki."

Hitsugaya's voice drew her attention. He was frowning at her, but that was nothing unusual. Karin realized belatedly that she had yet to jump from the gate's edge—he must have been waiting for her to go first or something.

"Hn." She pushed off the edge, launching herself out into open air. By this point, controlling her fall was child's play, and she landed softly next to Zaraki; Hitsugaya was right behind. Turning her eyes up, Karin watched the Senkaimon close, space gluing itself back together seamlessly.

Ground level was a neighborhood she recognized vaguely. Karin thought maybe it was somewhere between her dad's clinic—sold to someone else a long time ago—and what had been her elementary school. Easier than trying to remember where that was in relation to Urahara's place was just searching around for Yoruichi's reiatsu. Her weird gigai made it harder, but neither she nor that other guy Tessai were trying to conceal it.

"West," she said.

When they got there, Yoruichi and Tessai were waiting outside. The woman was leaning against the front of the shop, arms crossed over her chest. Tessai mirrored the body language, except he didn't lean. By the time they were within speaking distance, Yoruichi had pushed off from the wall and slid open the door behind her with a hand.

"They sent more of you than I thought," she said, glancing at each of them in turn. "Which one of you is in charge?"

"I am." Hitsugaya replied, taking a step forward. "Tōshirō Hitsugaya, captain of the Tenth."

Karin supposed that was probably for the best; there were only two captains here and the other one was Zaraki. He already looked bored.

Yoruichi appeared unsurprised. "Yoruichi Shihōin. This is Tessai Tsukabishi." She paused to allow Tessai to nod, then continued. "We can house you here, but it's going to be close quarters."

"That's fine."

It wasn't like they had anywhere else to go.

Yoruichi nodded shortly and turned, leading them all into the shop. The front room was unchanged; various sorts of candy made for colorful shelves—surprisingly tidy for a guy like Urahara. Probably one of the others did it. Everything was clean, but not especially well-used. They passed through to the back quickly, and Yoruichi ushered them all into a larger living room. Zaraki took up a spot against the wall, leaning his head back and closing his visible eye. Karin wouldn't be surprised if he'd decided to take a nap.

The rest of them squeezed in around a circular table. Tessai left with a nod at Yoruichi, who sighed.

"What else can you tell us about the situation?" Hitsugaya asked.

She shook her head. "Not a lot. I can share my guesses, but this isn't exactly my area." Yoruichi met Karin's eyes for a moment.

Karin understood.

"Any chance we can get a message to Urahara, or anything?" she asked.

"Believe me, I've been trying. He left behind a bunch of notes: on Hell, on Arrancar, on Aizen, even—but the parts I understand only tell me so much. I'll give you what I know, and what I guess, and you can decide what to do with it."

Karin huffed out a breath, falling back onto her rear and pulling her legs under her. Seiza was way too uncomfortable to maintain for long. "Lay it on us, I guess."

Hitsugaya shot her a vaguely-disapproving look; she shrugged at him. Yoruichi observed the byplay without comment, though her mouth did turn up at one corner.

"Sure." She took a deep breath only to sigh it right back out again. "Kisuke's notes indicate that an Arrancar can be made of any Menos-class Hollow. They're never complete naturally; but they can self-stabilize in an incomplete form. The Hōgyoku can make complete Arrancar, with full access to both their shinigami and Hollow powers. The ones we encountered even had zanpakutō; I'm assuming Aizen stole them at some point."

Karin had never heard of anything like that; but the other three at the table didn't seem surprised at all, so probably they had.

"Anyway, it seems like they can take various forms; of the two we fought, one was probably an Adjuchas. The other… I suspect the other was once a Vasto Lorde. I don't know how they measure up against anything else Aizen has, but if he was willing to send them out…"

"Then they probably aren't his closest underlings," Hitsugaya finished. Lifting his arms, he folded them over his chest. His eyes fell shut; a furrow appeared between his brows.

"Well, we know he's got Tōsen and Ichimaru," Renji said, shifting slightly awkwardly and glancing at Rangiku. "Maybe these are the next two guys down the ladder?"

"That's optimistic," Yoruichi said. "Think about it: this is Aizen. He's not the type to just throw his aces out at the start of the game."

Karin scowled. She hated the idea that he thought of it that way—like a game. She'd seen some of the damage the bastard had done just by betraying people, never mind this. But she guessed someone like that probably didn't care enough about anyone to think of it any other way.

"He would have used exactly what he needed to in order to accomplish his goal," Hitsugaya added. Opening his eyes again, he fixed them on Yoruichi. "Any idea what that was?"

She pursed her lips. "They weren't here very long. And they didn't seem very interested in fighting Tessai and I when we showed up. If I had to guess, I'd say they were more of a scout party than a vanguard. It's what I'd want to do—get the lay of the land first."

"So we're probably expecting more then?" Karin asked.

Yoruichi's reply was cut short by Tessai's return. He bore a tray laden with tea and snacks; no sooner had he placed it down than Karin and Renji dug in. She hadn't had breakfast, and the slight time-displacement in the dangai was always weird on her system. Rangiku waited until they'd cleared away before taking her own.

Hitsugaya abstained entirely. "If this first attempt was merely to gather information, then yes. I suspect we are."

"This is fuckin' ridiculous." Grimmjow stalked restlessly from one end of the room to the other. His Fracción watched him pace; Shawlong stood, one shoulder leaned into the doorjamb, hands in his pockets. The others sat either on the floor or the sofa, waiting.

They were waiting for him to tell them what to do. Sometimes he hated that about them; the way they hardly ever bothered giving their own damn opinions—the way they just followed. Gave up. Cowards.

When pacing was no longer enough to get rid of his restless energy, he started to grind his teeth. The muscles in his jaw jumped; the mask fragment on one side itched something awful. He flexed his fingers in his pockets sharply enough to crack the joints; a breath hissed out from between his teeth. All this damn quiet set him on edge in a way battle never did—he could feel it more keenly then. The roiling mass of souls that made him up. They didn't have any individuality anymore. They were just food. Fuel. But sometimes he swore he felt them clawing at his head, trying to get out.

"I can't believe that damn prick. There were enemies right in front of him, and what the fuck does he do? He runs away like a goddamn dog with his tail between his legs! And Aizen doesn't even do a damn thing!"

What was the point? Why let an enemy go when the opportunity to fight them was there? Didn't trying to hold all the power in drive him crazy? Grimmjow's nostrils flared. Self-preservation, maybe. Even he had those instincts. It was the reason he was here in the first place.

But his self-preservation instincts weren't nearly as strong as the rest of them. Yanking one of his hands from his pockets, Grimmjow dragged it down his face, fingers crooked so that his nails scraped over his hierro. Two of them hooked over the mask fragment—he pulled uselessly at it.

"We're going," he declared.

It was the only way he'd ever work out this restlessness. The only way he'd ever be himself.

Shawlong bowed slightly. The others stood at once. Not one of them argued with him. If they'd just agreed, that was fine… but even if they disagreed, they'd never say.

He hated it.

Shoving his hand back in his pocket, Grimmjow led the way from their quarters. Las Noches was stupidly-big, but all they really needed was a spot empty enough to call a garganta. The nearest one wasn't far away.

"You sure you want to do that?"

The lackadaisical voice could only belong to one person.

Grimmjow paused midstep, whipping his head sideways. Starrk's eyes were always dull like that—as if nothing ever interested him. It didn't make any damn sense to him, but at least the Primera wasn't a little shit like Ulquiorra.

"Why? Got a problem?" His eyes narrowed.

Starrk shrugged. "I don't really care what you do, but Aizen's not going to like it."

"He'll change his tune when I bring him shinigami heads on a pike." Grimmjow felt a familiar electric ripple over the surface of his skin at the thought of it. The restlessness began to subside.

"I don't think he will," the other Espada said evenly.

"You ordering me not to go?"

"Tch." Starrk uncrossed his arms and let them drop lazily to his sides. "Even if I did, it wouldn't make a difference, would it?"

It was a question that didn't really need answering.

Starrk sighed. "Be careful out there, Grimmjow. You shouldn't underestimate the shinigami." He blinked once and turned away, down a different hallway. Probably to find somewhere to sleep or something.

Careful wasn't in Grimmjow's makeup. Not by a long shot. Starting forward again, he turned into an empty room. It would do.

Time to prove once and for all that he was stronger than that damn Cuarta.

Well. Yoruichi hadn't been lying when she'd said space was going to be tight.

What was formerly one room had been divided into two with a screen, and the two parts together had to fit the five of them. Apparently Urahara's room was better not lived in—which was probably fair. Rangiku had only ever really learned about him in a secondhand way, but he was the man who'd thought the Twelfth Division was a good idea. There were probably all kinds of… things, in there.

She certainly had no intention of finding out.

The floorspace in the room was just enough for the necessary futons—all the rest of the furniture had been moved. Rangiku couldn't help but chuckle at the brief twitch in her captain's eye. She herself had grown up with considerably less space, so it wasn't really a big deal to her. Actually, it might be nice to fall asleep to someone else's breathing again.

Plus, she could have so much fun teasing everyone else.

"Karin-chan! You're sleeping in my half. It'll be great." She latched herself on to the much shorter woman's arm, suppressing her laughter at the flat look she got in return.

"Yeah… I'm sure it'll be a real slumber party," Karin drawled.

Rangiku blinked. "Slumber party?" She'd never heard of such a thing.

"Uh… never mind. Living world thing."

"People do this voluntarily?" Tōshirō asked, eyeing Zaraki suspiciously.

He did seem like the kind of guy who would take up a lot of space. Renji was pretty tall too, actually. Rangiku bit the inside of her lip, trying to keep a straight face.

"Some people," Karin corrected. "And… not quite like this. But it doesn't matter." Freeing herself from Rangiku's hold, she tossed her satchel onto one of the futons on the smaller side.

"Might be best if we got some shut-eye now, actually."

Renji had a point: they hadn't exactly slept the night before. Rangiku was used to late hours, but admittedly even she was a bit tired.

Karin frowned. "Shouldn't we do that in shifts? In case something happens?"

"No need," Rangiku said, digging around in her pocket. She produced a denreishinki, handing it to Isshin's daughter. "Renji probably forgot to get them to issue you one, but the rest of us have these. They'll make a lot of noise if there's a Hollow in the area. It should work for Arrancar, too, right?"

Tōshirō nodded. "Yes. But Kurosaki has a point; it makes sense for at least one of us to always be awake."

Karin blinked; Rangiku could read her confusion and the reason behind it as clearly as if she'd actually said the words. She probably expected Tōshirō to ignore her most of the time—to be fair, it was what he usually did. But this was a mission; and her captain took those seriously enough to put aside the worst of his cold shoulder tendencies.

"Uh… guys?" Renji sounded unusually hesitant. "Where's Zaraki-taichō?"

"What are you talking about, Renji? He's right…" Rangiku trailed off. Wait. Where was he? He'd been standing right there not moments ago—she could have sworn it.

"Uh…" Karin started.

She was interrupted by a shrill ringing sound from the denreishinki in her hand—and from the other two in the room. Her eyes rounded in surprise; she flipped open the screen. Rangiku leaned down to look over her shoulder. The radar showed several red dots at the same location, but within seconds they were separating from one another and spreading out.

There were six of them.

Kenpachi figured that maybe the meeting part of the deal was required, but he didn't really have the patience to sit around for the stuff afterwards. Not that he had anything against any of the people they'd brought—he wanted to fight Renji at some point soon, actually. And that girl—Karin or whatever—she had matches with Ikkaku sometimes. He liked the way she handled those.

But he wasn't here to talk strategy. All of that crap tended to fall apart the second he was in a real fight anyway. The only strategy Kenpachi bothered to use was 'hit it, and if that doesn't work, hit it harder.'

Considering how many fights he'd won, he figured it was a pretty good strategy.

Finding a fight was a little harder than he thought it'd be, though. The noisy thing in his hand was pointing him one way, but the bastards kept moving around, forcing him to change directions. It was worse than just doing what Yachiru told him—at least she didn't change her mind so damn often.

Which one of these assholes was the strongest, anyway? The den-whatever didn't tell him. It'd be really fuckin' annoying if he spent all this time running around and found some weak Hollow or something. Maybe his head start was enough that he'd be able to get close enough to figure it out before the others got there.

Maybe he'd get to take all of them at once before the others got there.

A grin stretched over his face. Now that was his idea of a good plan.

One of the red dots on the screen changed directions again; it looked like it was coming in his direction. That was good—if it was brave enough to come to him, maybe it would be strong enough to bother with.

Snapping the mechanical thing shut, he shoved it between the layers of his shihakushō and grabbed the hilt of his nameless, sheathless sword. Drawing it free, she raised it to block the incoming attack he'd barely registered, his body moving on instinct alone.

It met far more resistance than he'd been expecting, colliding with a kick aimed for his head. That was good—that was very good.

The Hollow who'd aimed it sprang away, landing casually on the ground. He had on some weird kinda white clothes and looked mostly like a human, but there was a pretty big hole right under his lungs. That and the piece of mask on his face made Kenpachi figure he was probably one of those Arrancar. Maybe he was really lucky and it was that Vasto Lorde one Yoruichi had been talking about.

That'd make Kenpachi's fuckin' day.

The Arrancar kept his hands in his pockets. Past the mask part, Kenpachi could see that he was smiling widely—pretty much the same expression he had, actually.

"Hey you," Kenpachi said. "You're an Arrancar, right?"

"And from that outfit, you're a shinigami," the other guy said.

He sprang forward, covering the space between the two of them quickly. Whipping his body around, he went in for Kenpachi's head with a kick. It had some stupid name to do with a building or something—Kenpachi didn't care what shit was called.

That time, he decided to let it hit, just to see what he was looking at here. It caught him square in the temple, snapping his head to the side. For a moment, the vision in his uncovered eye actually whited out.

This was great.

Swinging for where the Arrancar landed in retaliation, Kenpachi felt his smile stretch wider. His sword went through nothing but empty air. The heavy whistle stopped when he drew it back—his opponent still hadn't taken his hands out of his pockets, much less drawn his sword.

"Kenpachi Zaraki, Captain of the Eleventh Division," he said by way of introduction. He thought it was only polite to let a decent fighter know who was gonna kill him, after all.

"Captain?" The blue-haired guy grinned savagely. "Excellent. I'm Grimmjow Jaegerjaques, Sexta Espada."

Kenpachi had no idea what the fuck an Espada was—but since it didn't really matter to him, that was fine. Shifting his grip on the hilt of his sword, he tightened his fingers around it. "Are you the strongest guy here?"

"That's me," Grimmjow replied. "How about you?"

"Damn straight I am."

"Then I guess both of us are having a lucky day, Kenpachi Zaraki."

Kenpachi couldn't agree more.

Tōshirō could tell from the fluctuations in Zaraki's reiatsu that he'd found and engaged at least one of the Arrancar—a glance down at his denreishinki informed him that one of them had stopped moving completely. That left five in motion. He didn't really like the idea of taking on more than the number of people on his team, but at least Shihōin was with them. One-on-one matches with Hollows this strong wasn't the wisest thing, either, but they had little choice.

It seemed to be the strategy the Arrancar were employing as well—where they'd started to split, now they converged again. Their course was obvious; they were going to meet Tōshirō's party head-on.

All five of them appeared at once. Shihōin reacted the fastest, springing into the air and kicking one of them off his course, away from the rest. With a jaunty salute, she followed, flashing away with the speed he'd expect of someone once given an epithet for the technique.

The ones that remained landed about ten feet from his group. The one front and center had a strange Hollow mask that capped his head and protruded out to his right. The largest had a bright red mohawk, And the other two were a rotund Arrancar with a mask that still covered half his face and a thinner blond one.

It was difficult to differentiate their reiatsu when they were all standing that close together—they all had a similar feel for some reason. But he was pretty sure the one in the middle was the strongest.

"Hey Hitsugaya. I'll take the big guy." Kurosaki pointed at the one with the red hair.

The Arrancar in question folded his arms and smirked. "I guess you're eager to die, little girl."

She clenched her jaw. "Maybe. Wanna find out?" Kicking off the ground, Kurosaki angled herself away in the air, leaving plenty of room for everyone else to fight.

The Arrancar followed.

Renji glanced at Tōshirō and shrugged. "Any preference?"

Considering he had no idea what abilities any of them had, he simply planned to deal with the strongest. "The leader."

"All right. Blondie, you're with me."

Apparently the Arrancar were amenable to splitting up in any fashion, because those two moved away as well. Considering that, there was only one thing to conclude.

"There's no specificity to your targeting. You're just here to kill anyone who gets in your way."

The man in front inclined slightly. "Just so," he said mildly. "As from your manner of dress I assume you're in charge here, I suppose you will be wanting to fight me, yes?"

Tōshirō reached back for Hyōrinmaru's tsuka.

"How observant of you."

What the heck was with this guy? It was like her sword couldn't cut him.

Hisaku's sealed blade clanged off skin as hard as metal; Karin flashed away before he could punch her in retaliation. Considering that was the third time something basically the same had happened, she figured there was no need to mess around any longer.

"Sobiero, Hisaku!"

Drawing her blade in a swift motion, Karin lunged, aiming for the Arrancar's shoulder. The fire released with her shikai hit him first—the blade itself was a second later. Still, he resisted it; Hisaku left a cut in him this time, edges blackened, but it was shallower than it should have been.

He glanced down at it, as if surprised that she'd managed to make him bleed. He opened his mouth—probably to say something—but Karin honestly wasn't interested in hearing it.

"Sakebe."

A dull roar filled her ears, competing with the sound of her heart. Hisaku lit on fire; Karin channeled her reiatsu into the blade, focusing on sharpening it to as fine a point as possible. It was a lot like that time in Hell. Except… if she killed this guy, he wouldn't just pop back up a couple hours later.

She swallowed, then shot forward.

The strike she aimed for the Arrancar never connected; he stepped aside to avoid it, then brought both fists down together. The blow caught her right in the back; it was only a second later that she crashed facefirst into the roof of the building below.

She heard a wet crunch at the same time as she felt a terrible pain in her face. It took a moment, but the blood seeping out of her mangled nose told her she'd definitely broken it.

"Shit." She could taste it on her tongue, too.

Karin pushed herself to her feet—she'd definitely be mostly purple tomorrow morning from all the bruises she'd just earned. But she was damn lucky nothing else had broken, or she'd have worse problems right now than being forced to breathe out of her mouth. Her legs protested when she used shunpō to avoid the follow-up and get back in the air; she had no choice but to suck it up and deal.

She couldn't let herself get hit like that again if she wanted to live. Which meant she had to move too fast for him to catch her.

"Tobase."

Sucking in a breath, she relished in the feeling of lightness the technique produced for only a second. Wary of getting in too close, she flung fire arcs from Hisaku's blade instead, keeping herself in constant motion so she wouldn't make an easy target. The fire wasn't doing a lot of damage, but it did some. Enough that parts of the Arrancar's skin were reddening and blistering, anyway.

But she could already feel herself tiring and slowing down; that damn limiter was a pain in the ass. Rangiku had put in the request to get them released on their way over—but if this guy got her even once more, she might not make it that long.

"You call this fire?" the Arrancar taunted. "I can barely feel it."

Karin bit her tongue against the automatic instinct to taunt back. The more bored he was right now, the better. The last thing she needed was for him to get serious while she still had the limiter on.

"Come on," she muttered to herself, throwing three more lashes from different angles.

He just stood there and tanked all of them. She grimaced; she was splitting her reiatsu too many different ways. Letting the Tobase technique go out, she pulled the flames at her feet back to her sword, pumping more reiatsu into the fire there. It flared, the red color of it brightening to scarlet.

"This is pathetic," the Arrancar said. "Get out of my way so I can kill your friends."

At the words, he reached to his sash, laying a hand on the hilt of his sword. "Okiro, Volcánica."

When she'd heard that Arrancar had zanpakutō, she'd figured that meant they'd work in a basically similar way. Karin was not expecting that at the end of the process, her opponent would look a lot more like a Hollow. He was pretty big—an Adjuchas, most likely. His arms were huge for his body, and they had what looked like vents or something cut into them. Smoke curled out of the gaps, thick enough that she was glad she wasn't that close.

Oh great. This was gonna be a pain.

"What the hell is that?"

One minute, he'd been fighting a humanoid Arrancar.

Now, he was staring down a giant… Hollow? But he still also kind of looked like a human? Renji wasn't sure what to make of it, but he wasn't liking the massive reiatsu spike that came along with the transformation. That was not great news for him.

"This? This is how we Arrancar release our zanpakutō, brother." Yylfordt—Renji was fairly sure that was his name—tilted his head.

It was pretty obvious that those horns were the main way he attacked in a form like that. Renji lowered his stance, holding Zabimaru in a one-handed grip directly in front of him. His other hand, he kept free for now.

"Oh yeah? Is that so?" He spoke more to buy time than because he was curious—but the information would be good if he could get it.

How much longer was it gonna take to get the damn seals undone?

"It's called," Yylfordt paused, bracing himself on the ground. "Resurrección!"

He charged. Renji had expected that much. What he hadn't expected was just how fast he'd be. Unable to dodge, he raised Zabimaru to block; a dull clang sounded out when he successfully staved off one of the incoming horns.

The other broke skin between his neck and shoulder. Renji strained to push back; the effort shook his arms. Even without momentum, Yylfordt's strength was enough to keep pushing forward—centimeter by centimeter, the horn dug in to Renji's muscle. Gritting his teeth, he adjusted his feet and stepped out wide, breaking the deadlock and sending Yylfordt pitching forward. He recovered too quickly for Renji to press the advantage, and the horn left a broad slash on his strong side.

Yylfordt charged again; this time Renji was a little more prepared. He was slower than the Arrancar with his limiter on, so he had to make sure he didn't need to move far. Timing his motion, he just barely got out of the way of the charge—one of the horns sliced through part of his shihakushō. The second the dangerous part was past him, he retaliated, lashing out with Zabimaru's greater range. The segmented blade struck the back of Yylfordt's neck, where he'd aimed, but bounced off; it left only a shallow cut behind.

Apparently, all the Arrancar's abilities had gone through the roof when he released his zanpakutō.

"Renji!" Matsumoto's voice reached him over the noise of nearby battles. "Authorization came in!"

As if to prove her right, the camellia below his left collarbone disappeared when he struck it. The reiryoku it had kept sealed flooded back into his system all at once; he pushed out a heavy, relieved breath. Much better.

"Looks like we can stop messing around," he muttered, mostly to himself. Yylfordt charged again—avoiding it was much easier this time.

Renji really wasn't in any kind of mood to be prolonging the fight—that was for spars and friendly matches, not this kind of situation. With the energy he'd just gained, he should be able to get it over with. Should be a good opportunity to field test something new, too. He half-smiled at Yylfordt, eyes narrowed to slits.

"Sōō Zabimaru. Bankai."

Term Dictionary:

Volcánica – 火山獣 – The kanji read "volcanic beast." The pronunciation is the word "volcanic" in Spanish. Eduardo's resurrección. The release command is okiro (起きろ), which in context is "blaze up" or surge in the fire-specific sense. Since we're talking about a volcano, "erupt" is the best match in English. Eduardo can control fire/heat via his fists when it's released.

Resurrección – 帰刃 – The kanji are "returning sword," while the Spanish is "resurrection." I'm treating this slightly differently from canon; an Arrancar can only seal their powers in a zanpakutō, and it works a lot like a shinigami's pattern of release. Unlike most shinigami releases, however, a resurrección usually alters the Arrancar's physiology more than their weapon. More on that… eventually.