#although it is wholly different from the Miles Electric Juice mentioned therein

[sage-nebula]

STH — Beyond Oblivion, ch.1

Notes: Six days ago I made this post, wherein I talked about being inspired by @chaoxfix's works (specifically "build away and away and away", which is fantastic and you all should read it) to think of a world where Sonic didn't exist, and so Eggman raised Tails instead. I couldn't stop thinking of the idea, and so here we are, the first proper fic I've written in a while. Thank you, Chaofix, for the inspiration; it feels nice to really write something after so long.

This is still rough; I'll probably clean it up later before putting it on AO3. But until then, here's chapter one. Fic title comes from this song from the Neo: TWEWY soundtrack.

Summary: After an accident with what is believed to be a fragment of the Phantom Ruby, Sonic is catapulted into a world where he never existed, leaving Tails to be raised by the one person who should never be put in charge of children.

— — —

“Wow. That’s the biggest chunk of ugly red rock we’ve found yet. Think it’s real?”

“Not sure. I’m scanning its composite signature now so we can compare it to that of the real ruby. We should know in a few minutes.”

“Gotcha. Thanks, li’l bro.”

“No prob—hey, did you see something move over there?”

“Huh? Where?”

“On the other side of the—isn’t that Shadow’s chao?”

“Shadow’s chao? What’s that doing her—hey, stop!”

“Is it trying to take the ruby?!”

“Not if I have anything to say about—”

“Sonic, don’t—!”

Sonic’s eyes shot open.

Above him was a dismal grey sky thick with clouds, a stark contrast from the clear blue of before. Under his back was dying, yellowed grass, scratchy against his quills and so different from the sweeping green plains he and Tails had found the Phantom Ruby chunk in moments before. When he closed his eyes, Sonic could see the chunk of ruby glistening in the dirt, the tiny black paws of Shadow’s chao reaching for it. Sonic could see his own hand reaching out, pushing the chao back . . . and his knuckles swiping across the gleaming, glowing stone.

Sonic snorted as he opened his eyes again.

Well, that answered the question of whether the ruby chunk was real or not.

He sat up, and rolled his shoulders to work the stiffness out of them. It felt like only a second had passed, but the throbbing through his body suggested otherwise. There wasn’t much around him; a parched plain stretched for miles in any direction he could see, barren trees dotting the landscape here or there and what looked like a rocky mountain range in the distance. It was . . . wrong. Sonic didn’t know where he was, but he knew that it was wrong. The grass, the trees—they shouldn’t look like this. And the wind, growing stronger by the second, stank of exhaust even though there weren’t any cities around for—

Sonic jolted to his feet as a foghorn blared, setting his every quill on edge. For a half second, he had no idea where it came from; but as the rank aware gusted around him in a cyclone, he finally turned his eyes back up to the dismal sky, and felt both recognition and revulsion at once.

“Huh,” Sonic muttered. “Didn’t realize he put it back in commission.”

Eggman’s airship—the Flying Battery.

A gargantuan mass of steel and gunpowder, the Flying Battery was, at one time, the military flagship of Eggman’s would-be empire. Boasting more cannons than badniks, the Flying Battery was meant to rain unrelenting missile fire onto the world below, and smog into the sky above. Not that it had much of a chance, of course; Sonic had wasted no time (but had plenty of fun) ripping it apart from the inside out before he sent it careening to a fiery demise.

Yet here it was again, leisurely wading through the clouds as it trailed smog and—Sonic realized, the ground pulsing beneath his feet—bad music behind it. Because the throbbing he had felt before wasn’t coming from inside him, but from inside the ship above his head; a pulsing beat radiating over the empty plain.

Sonic frowned, and tapped his foot.

He didn’t know where he was. He was only vaguely sure of how he got there. And one look his wrist communicator, which flashed a dead signal message back at him, told him he wasn’t going to be able to call Tails for a lift back home any time soon. But no matter where he was, there was never a bad time to bring down a megalomaniac’s prized warship.

Sonic grinned, and sped off after it.

- - -

Hitching a ride on the Flying Battery was as easy as it ever was, if a bit slow for his tastes. All he had to do was wait for it to pass by the mountain peak where he waited, and then take a flying leap. Easy as pie, none of the security sensors so much as twitched a cannon in his direction.

If he was honest with himself, Sonic would say he was a little disappointed.

The Flying Battery was much as it had been before, albeit with a few more clucks guarding the corridors than he remembered. The curious thing Sonic noticed as he smashed each and every one to bits was that not a single one had an animal powering it. As yet another technosqueak broke apart against the wall, not a single flicky or ricky scampered out. And they weren’t concussed, either, as sometimes happen when a bot bash was particularly rough; Sonic took care to pick through the pieces of broken machinery, and found not a strand of fur or loose feather for his efforts.

Weird. But not unwelcome.

The badniks were sparse, anyway. It was how it had been in the past, too; the Flying Battery boasted traps and cannons, with badniks being put to use as shock troops and foot soldiers down on solid ground. It was for this reason that Sonic was able to make his way to the engine room pretty quickly, even for him, leaving a trail of smashed cannons and broken badniks in his wake. He roughly remembered where it was from the last time he was on the ship, but even if he hadn’t, it wasn’t hard to find; the thumping bass audible from the earth below only got louder the deeper into the ship he went, and outside the engine room door it was so powerful it rattled his ribcage from the inside out.

Sonic grimaced. His ears were going to hate him for this later.

The second the door to the engine room slid open, the pounding bass transformed into blaring EDM. On instinct to protect his hearing, Sonic clapped his hands over his ears and scanned the room. The engine room didn’t look much different from how he remembered it. The engine itself was situated dead center, taking up most of the available space, and the music was blasting from a speaker in the upper right corner of the room. But as much as his first instinct was to throw a couple quills through the center of the speaker to shut the noise off, what caught his attention in a lightning-fast vice grip wasn’t the music at all, but instead the fluffy orange fox tails poking out from behind the engine.

Sonic slowly lowered his hands from his ears. “Tails? Is that you?”

The tails—Tails’ tails—twitched, but otherwise there was no movement from behind the engine. Before Sonic could call out to him again, though, the music’s volume jumped up another few decibels. Sonic’s eyes widened, his jaw dropped a little in indignation.

Did Tails seriously just turn up the music to drown him out?

Sonic scanned the room, but there was nothing immediately available that suggested a control for the speaker. That being the case, he settled for the next best thing; in two bounds he cleared the room and up the wall, and with one solid yank he pulled the cords connecting the speaker to the wall loose. The music cut out instantly with nothing but a sputtering crackle for its efforts, and in the newfound silence in the room (and ringing in his ears), Sonic heard metal clang to the floor behind the engine.

“Ugh, are you serious?” Tails—and that was definitely Tails, Sonic would recognize his voice anywhere—snapped. Sonic hopped back down to the floor as Tails, lying horizontal on a metal scooter, slid out from behind the engine. “I swear, there better be an emergency for you to—”

Tails’ voice died in his throat as he sat up and looked in Sonic’s direction, and Sonic didn’t need to see the eyes behind the welding goggles to recognize Tails’ shock. He grinned, and raised his hand in a wave. “Hey buddy.”

Tails said nothing. He moved his welding goggles up to the top of his head, and continued to stare at Sonic for a moment, his expression uncomprehending. Then, before Sonic could do or say anything to break Tails from his stupor, Tails frowned and bounded up off his scooter, circling Sonic with a look of intense concentration.

Sonic raised his eyebrows, bemused, as Tails poked one of his quills. “Uh, bud—”

“What are you?” Tails asked, and before Sonic had a chance to laugh at the ridiculousness of the question, he continued, “You’re definitely not a robot, or at least not one of the Doctor’s models. You don’t look like one of Dr Starline’s either, unless . . .” Tails, now standing in front of Sonic again, frowned as he met Sonic’s eyes. “Are you a cyborg? But no, that doesn’t make sense. There’s no way his experiments have progressed to the prototype stage yet, especially since I’m supposed to be—”

“Whoa, whoa, slow down.” Sonic held his hands up, and Tails, still frowning, took a step back. “I’m not a robot, and I’m definitely not a cyborg. I’m 100% pure hedgehog.” As Tails’ dubious frown deepened, Sonic patted his hand over his heart. “Tails, it’s me. Sonic. Don’t you recognize me?”

The moment the name Tails left Sonic’s mouth, Tails scowled, his hackles raising slightly over his teeth. “I’ve never seen you before in my life. And you’ve obviously never met me, otherwise you’d know my name is Miles.”

“Well, yeah, your first name is, but . . .” Sonic frowned as Tails turned back toward the engine. “Wait, what are you talking about, you’ve never seen me before? I’m your best friend.”

Tails scoffed. “I don’t have friends, much less a best one. You’re thinking of someone else.”

Sonic opened his mouth to point out how ridiculous that was, but closed it a second later. Now that he got a better look at Tails, something was definitely wrong (and that was an understatement considering Tails had been working on the engine of one of Eggman’s warships, but besides that). He was Tails, unmistakably, but with differences, like he was one of those “spot the differences” picture puzzles. His fur was orange, but grimier and matted in a few different places, such as clumps behind his knees and around his elbows. His eyes were blue, but the right one had a strange, glassy look to it, and caught the light oddly depending on how Tails tilted his head. More alarming was the chunk that was missing from the outer edge of his left ear, as though something had jammed straight through it and ripped a piece off. His gloves were black with red trim, and instead of sneakers he had donned a pair of work boots. Which, whatever, if he was working instead of running—but Sonic had never seen him wear boots like that once in his entire life. And considering Sonic himself had practically raised him, that was saying something. This was Tails, but it wasn’t Tails. Which meant—what? Had the Phantom Ruby sent him to another dimension? But couldn’t it only do that when used with the Chaos Emeralds? And it wasn’t even the whole ruby, so why—

Tails groaned, breaking Sonic from his thoughts, and rubbed his forehead between two fingers. “I have a headache. And what did you do to the speaker?” Before Sonic could answer, he looked up in its direction, scowling at the dangling wires. “Did you just rip them out?”

“Yup,” Sonic said, and popped his lips on the “p”. Tails turned his indignant stare on him; Sonic stared unrepentantly back. “And it’s a good thing I did, since the ear-shattering volume you had it on is probably why you have a headache.”

Tails rolled his eyes. “No, I just haven’t had a chance to eat today. And now that I have to fix the speaker on top of the modifications to the engine, I won’t be able to eat until even later. So thanks.”

“The speaker and the engine can wait. Food comes first, always.” Sonic put out a hand to stop Tails from making it to the toolkit open beside the engine, but Tails batted his hand away.

“Maybe wherever you come from, but not here.” Tails paused, and scrunched his nose as he looked back up at Sonic. “Where did you come form, anyway? How did you get up here? If you're not a robot or a cyborg, there’s no way you made it up here. Am I hallucinating?”

“Do I look like a hallucination?” Sonic asked, and before Tails could answer, he poked Tails’ cheek. Tails swatted his hand away again. “Nah, I just jumped on when you passed by those mountains down there. Easy-peasy.”

“‘Easy-peasy,’” Tails repeated flatly. Sonic nodded, grinning, and Tails shook his head as he knelt down beside his toolkit. “Well, go jump back down onto the mountain, or wherever else you can go that’s not here. I’m busy.”

“And leave you here? Yeah, no dice,” Sonic said. Because Tails might not have been his Tails, but there was no reality Sonic could think of where he’d just leave Tails by himself on an Eggman warship. “What are you doing here, anyway? And what happened to your ear?”

“I work here,” Tails said, like it was the most obvious thing in the world. His left ear twitched when Sonic mentioned it, but he otherwise ignored the question as he pulled a pair of wire cutters out of his toolbox.

“For Eggman?” Sonic barked a laugh. “Come on, get real.”

Tails shot Sonic a weird look before he spun his tails to gain altitude, hovering up near the broken speaker. “Who’s Eggman?”

“Uh, the megalomaniac who owns this warship?” Sonic said, and when Tails gave him another strange look, spread his arms wide. “Big guy. Bald head. Orange mustache. Makes a lot of ugly robots and tries to take over the world with them.”

“Oh, you mean Dr Robotnik.” Tails used the wire cutters to clip away one of the broken cords of the speaker, and tossed it onto the floor. “Why’d you call him ‘Eggman’?”

“Beeecause that’s his name?”

“No it’s not.”

“Well, it is where I’m from.” Sonic crossed his arms and tapped his foot as Tails dropped another clipped wire to the floor. “But whatever, doesn’t matter. You can’t seriously be telling me you work for that guy.”

“I can and am, because I do. Have since I was like, four.” Tails scowled at the back of the speaker. “Could you have done a worse job on this? You tore part of the connector off halfway. This is going to be so annoying to fix.”

“That’s the least of my concerns right now,” Sonic said, as Tails dropped back down to the floor. He reached out a hand to steady Tails as Tails stumbled, but once more Tails ducked under his hand and made his way to the toolkit. “What do you mean, you’ve worked for him since you were four? Where was I?”

“I don’t know, where were you?” Tails quipped, as he dropped the wire cutters back into the box. Sonic fought the urge to roll his eyes, and channeled his energy into tapping his foot instead.

“Look, Tails—”

Tails whipped back around to look at him, gaze burning. “Miles.”

Sonic returned his stare in kind. “Look, Miles. I don’t know what’s going on here. Frankly, I’m not even from here and from the looks of things so far I don’t wanna be—”

“Then leave.”

“—but this whole situation?” Sonic gestured to Tails, and then the engine room at large. “Is messed up. And I’m not leaving here without you.”

“Then I guess you’re not leaving, because I’m stationed on the Flying Battery at least until it docks tonight, and probably even later if I don’t finish the engine modifications by then.” Tails dug a few black cables from among the loose parts in the bottom of the toolkit. “But you should know that Dr Robotnik is going to be waiting at the dock so he can check over my work, and if you’re here he’s not going to be happy since I’m the only sentient thing authorized to be on the ship right now. So it’d really be better for both of us if you got out now, or at least within the next hour.”

“‘Sentient thing?’ I think the word you’re looking for is ‘person,’” Sonic said, but Tails ignored him, still rummaging through the toolkit. “But sure, I’d be happy to leave. I finished just about everything I wanted to do before I came in here anyway. So once you’re ready to go, just say the word.”

“Everything you wanted to do?” Tails furrowed his brow, and then sat back on his haunches as he looked up at Sonic. “What do you mean? Why are you up here, anyway?”

“Oh, you know,” Sonic said vaguely, and he folded his arms behind his head as he grinned. “Seeing the sights, trashing the place. The usual.”

Tails snorted, and turned back to his toolkit. “Yeah, okay. Good joke.”

“I’m not joking,” Sonic said, and when Tails made another disbelieving sound in the back of his throat, added, “I smashed every cannon and badnik on the ship before I made my way back here. I went through every room. You can go see for yourself if you’d like.” And then, as soon as he was in the open air, Sonic would grab him and jump ship. Not that Tails needed to know that, of course.

“Yeah, sure. And then you can get a good laugh while I waste even more of my time looking at a perfectly in-tact warship.” Tails peered at another pair of cables before evidently deciding they weren’t good enough and dropping them back in the box. “No thanks.”

Sonic couldn’t help it; he laughed. “I’m not—”

“Look, I don’t know you. And I know you don’t know me.” Tails finally stood up from the toolkit and looked back at Sonic, who once again felt an uneasy swoop through his stomach at the odd way the light glinted off his right eye. It was almost as if it wasn’t— “But I’ve been a sysadmin of the Robotnik Empire since I was four, and chief mechanic for almost as long. I’d know if something was going wrong on this ship. I installed all the sensors and alarms myself.”

“Then you might want to double-check ‘em, because either they didn’t work or your music drowned them out,” Sonic said flatly, fighting against the bristle in his quills at Tails’ stated life story. “Because I’m telling you, I trashed the whole ship on my way here, and had a good time doing it, too.”

Tails rolled his eyes. “You’re lying—”

“I’m not,” Sonic interrupted. “I would never lie to you.”

Tails watched him for a second before he sighed, and shook his head. “Okay,” he said, and gestured for Sonic to follow him as he looped around the front of the engine. “Come here, then.”

Sonic followed, and watched as Tails brushed his fingers along the metal countertop jutting out of the left wall. Instantly, the steel paneling in the wall flared to life, revealing itself to not be paneling at all, but a wall of computer monitors, ten in total. The countertop gleamed with a luminescent keyboard, across which Tails’ fingers skipped as he entered in a username and password.

“This is the central processing mainframe of the entire ship. All of its artillery, security systems, and defenses are controlled through here,” Tails explained. He didn’t once look back at Sonic as he did so. “And if something happened to damage any component of the ship, not only would I be able to see it from here, but alarm would have . . . been . . . trigg . . .”

All ten monitors connected to a different security camera around the Flying Battery, and while each one focused on a different area of the ship, each one showed a similar level of carnage. Pieces of badniks were strewn across the corridors. Cannons smoked feebly where they had been destroyed. Lights were shattered and dangling from the ceiling by half-torn cords.

“This . . . this can’t . . .” Tails switched the feed on a few of them, tapping into different cameras around the ship. More than one of them returned nothing but static to their feed. Sonic examined his fingernails.

“Told ya,” he said, as Tails frantically opened another program on the computer. “I’m very thorough.”

“I didn’t hear it,” Tails whispered, staring in horror at the list of ignored warnings and alerts his security program now displayed. “The security system did go off, it did alert me, but I . . . I didn’t hear it, I didn’t notice.”

“See, that’s what happens when you play your music too loud.” Sonic tsked his tongue. “I’ve told you before, buddy, you’re gonna blow your ears out one of these days. Music is just as enjoyable at a normal volume. Maybe even more so.”

Tails wasn’t listening. He splayed both hands next to his keyboard, leaning forward with his head bowed. “It’s gone. It’s all gone. Everything, destroyed. The whole ship is destroyed. I haven’t finished modifying the input-output ratio of the engine, but that doesn’t even matter because the artillery and defense systems and everything on the entire ship has been destroyed and I—I just let it happen, I didn’t even notice, someone infiltrated the ship and destroyed it and I didn’t even notice—”

Sonic frowned. Tails’ breathing was shallow and quick, tremors starting to wrack through his body. “Whoa, Tails—”

“And now it’s wrecked, and—and—and destroyed, and in pieces and we dock in an hour, in less than an hour and I have nothing—I have a—have worse than nothing to show for it, because at least if I had nothing it would be at the—at the baseline, sa-same as it was before, and that wouldn’t be great but it would be better than having less than nothing because everything is destroyed and broken and ruined and this isn’t possible or acceptable and he’s gonna be furious—!”

“Tails!” Sonic grabbed Tails’ shoulders, in an effort to ground him, to steady him, but Tails flinched and yanked himself out of Sonic’s grasp, stumbling back against the countertop. “Stop, okay? Breathe. You’re gonna be—”

“I can—!” Tails’ voice broke off in a squeak, and then violent coughs; he doubled over, and wrapped his arms around himself as choked over gulps of air. Once more Sonic reached out to steady him, and once more Tails stumbled back, away from his touch. “I can’t—I can’t—I ha-have to—”

“Breathe,” Sonic said, and when Tails’ eyes flicked to him, he took a slow, deep breath, and then exhaled it just as slowly. “Just like that. In, and out. Nice, slow, and—”

Tails screwed his eyes shut, and yanked his ears down against his head, squeezing them tight. “Don’t—don’t tell me what to do! This is your fault! You did this! You—you broke everything, and wrecked it, and we dock in an hour and Dr Robotnik is going to see it and I—”

“You aren’t going to be here,” Sonic said firmly, even as Tails shook his head, releasing his grips on his ears to tug one of his tails around him instead. His grip on it was like iron. “Egghead can think whatever he wants, but he can think it far away from you. We’re leaving.”

“No.” Tails continued to twist his tail in his fist, in a way that honestly looked like it would be painful to Sonic, and chewed hard on the fingers of his other hand, his eyes darting around the room. His breathing was still quick, and Sonic noticed punctures in Tails’ glove now that looked like they’d been made with his own teeth. “No, no, I can—if I work now, and have a boost, then I can—I can fix it, or at least most of it, at least the actual structural damage to the ship before we land, and then he never has to know that I screwed up and ruined anything and that I’m not useful anymore—”

“Tails—”

“—and—and everything will be, it’ll be, I can do it, I can, I can—” Tails flew the short distance back over to his toolkit, and unceremoniously dumped it over, spilling tools and loose parts over the grated floor. A peal of frantic giggles escaped him as he picked a vial of glowing magenta liquid off the floor, and tossed the toolbox over his shoulder. A shiver raced up Sonic’s spine. “Yes, yes, this can work, it can—I can—”

“Wait, Tails—stop a minute, okay?” Sonic grabbed Tails’ wrist, and as if on instinct Tails threw his entire body weight to the floor, twisting to get out of Sonic’s grasp. Sonic didn’t let go. “Just—stop. What is that you have? It looks like the junk from Eggman’s chemical plant.”

Tails gave Sonic a baleful stare. “It’s a performance enhancement serum developed by Dr Starline. If ingested orally or intravenously, it shuts down pain receptors, heightens muscle strength and elasticity, and enhances adrenaline output to—hey, what—what are you doing?!”

Tails’ voice broke off in a shriek as Sonic swiped the vial from his hand and threw it hard against the opposite wall. The glass shattered, and its contents oozed down the wall and onto the floor.

“Nothing made by Starline has any business being anywhere near you,” Sonic said, fighting to control his own temper as Tails stared in horror at the ooze on the wall. “Shutting down pain receptors? Enhancing whatever? Were you listening to yourself?”

“It’s the only way I can fix anything,” Tails said in a tiny voice. Sonic’s anger started to fade as he felt Tails shaking in his grasp. “It’s the only chance I have and—and you—you broke that, too—”

Sonic sighed. “Nothing here needs to be fixed, aside from the fact that you’re still here when you really shouldn’t be. Come on, we’re bailing.”

“No.” Tails threw his weight hard against Sonic’s grip as Sonic tried to pull him up from the floor. Sonic gritted his teeth, and swallowed down any guilt that started to well up at the tears that started to pool in Tails’ left eye. “No, you’re not—you’ve done enough, stop, stop trying to make things even worse—”

“I’m not making things worse, I’m trying to help—”

“You’ve destroyed and ruined everything—!”

“I haven’t—”

“Just stop and let me go, let me go, let go, let go, let—!”

“No, I—ow, Tails—!”

Tails kicked Sonic hard, the sole of his boot connecting with Sonic’s knee hard enough to make him stumble and loosen his grip. Tails didn’t waste a second; he twisted free of Sonic’s hold and dodged around him, sprinting for the door.

“Oh no you don’t!”

Tails barely cleared the doorway before Sonic was on him. Sonic wrapped his arms around Tails in a bear hug, and in an instant Tails thrashed in his hold, kicking both feet back against Sonic’s legs and twisting around as hard as he could manage it.

“Damn it, Tails, just listen—”

“No, let me go!”

“So you can try hiding in an air duct or something? Not likely. We’re leaving.”

“No! You can’t make me!”

It was so childish Sonic might have laughed, were it not for the way Tails was digging his elbow into Sonic’s ribs. “Wanna bet?”

A wordless, furious growl escaped Tails instead of an articulate response, and for just a moment, he slowed his struggling. Sonic loosened his grip a tad, hoping that maybe Tails had tired himself out and was going to see reason—only for Tails to twist around and sink his teeth into Sonic’s arm.

He bit him. He actually bit him!

Sonic yelped and released Tails, who dropped to the floor in an undignified heap. But he once again wasted no time; he scrambled to his feet and took off down the hall, tails whirling to boost his speed.

Oh, that was it. Sonic’s patience was officially gone.

He tore down the corridor after Tails, who—despite using his tails to increase his speed—only managed to make it around one corner and halfway up to an air vent in the ceiling by the time Sonic found him. Sonic snorted. Predictable. Tails whipped around as Sonic neared, and held the vent cover between them like a shield.

“For what it’s worth,” Sonic said, “I really don’t want to do this. And I’m sorry in advance.”

Tails narrowed his eyes. “Don’t want to do wha—?”

Before he had time to finish his sentence, Sonic zipped under and behind him. And before Tails had a chance to turn, Sonic skirted up the wall and knocked his elbow into the pressure point at the base of Tails’ neck, near the top of his spine. The vent cover clattered to the floor as Tails went limp, and Sonic caught Tails in a bridal carry just before he hit the floor.

“Sorry, bud. But this is for your own good.” Sonic shifted Tails into a more comfortable position in his arms, and after a millisecond of consideration, placed a quick kiss to his little brother’s forehead. Then he set off to find a parachute, so they could leave the Flying Battery behind them.