Sokka felt no small sense of justified smugness, watching the glacier (okay, it wasn't the whole glacier, clearly, but a hefty chunk of ice nonetheless) part to let Zuko's ship slide into the interior. Katara could probably do that if she was on a social justice rant of some kind, and knew where to apply pressure.
Watching the elderly woman overseeing both her team and the process with smooth movements – General Yugoda, he remembered Arnook saying – Sokka also felt a vague sense of apprehension, imagining the true terror Katara could be with a little honing of her hydrokinesis. But for now, he'd just be happy to see his sister.
Internally, because he had a reputation as a suave smartass to maintain.
Unlike Zuko, who dashed towards his ship the second its prow crossed the threshold, and jumped onto the gangplank before it was even properly lowered.
Following at a more leisurely pace, for the sake of both his dignity and Princess Yue, Sokka heard the loud sounds of an excited Toph and Aang and the worry-tinged notes of an angry Katara. Yeah, Sokka was going to let Zuko take the tongue-lashing for that one. The icy swim under hostile waters had been his idea after all.
"I'm not saying you'll like them," Sokka commented to Yue, who managed to make even a giggle sound dignified and royal. "But hopefully you won't hate them."
"I must admit I'm very curious to meet the children. It's not often one meets an elder that is actually younger than you!"
"Trust me, they don't act like elders," said Sokka, dryly, and almost got bowled over by the whirlwind that was Aang.
"Sokka! You're okay! Katara was worried. Your scroll said you went hunting, but nothing to hunt!"
"Message, or note," Sokka corrected automatically. "And there's plenty to hunt on the ice if you know what to look for. Aang, this is Princess Yue. Princess Yue, Aang. His creole isn't great yet, sorry about that."
"Honored to meet you!" cried Aang, with a little bow, and Sokka rolled his eyes. Of course with Zuko as a teacher, one of the first words Aang had learned was honor. And now the little airhead was using it to show up Sokka's statement about his language capacity.
"It's an honor to meet you, too, Aang." Yue was the picture of grace, and a picture Sokka wouldn't have minded staring at extensively under different circumstances. But what with the looming threat of a Fire Nations invasion, and Sokka about to get yelled at by his sister, that was wishful thinking.
"Sokka, I hope you're –" Speaking of sisters. Katara caught herself with a stutter, cheeks suddenly flushed red. "Oh. H-hello."
"Hi," breathed Yue, and Sokka felt the overpowering urge to hit himself in the forehead, hard. "You must be Katara."
"Yes. That's, uh, that's me. Who are – Sokka, introduce us!"
Since when did Katara care about being proper? Although anyone who looked at Yue could tell at once that she was a dignified woman. Sokka sighed, greatly put upon. "Katara, Princess Yue. Princess Yue, my sister and the occasional bane of my existence, Katara."
Wow, he'd gotten not one but two women to blush at that. He'd be patting himself on the back for his flirting prowess if one of them wasn't his sister.
"You're the hydrokinetic, right? I'd be happy to accompany you to meet General Yugoda."
"How is there dirt fucking everywhere? I was gone for twenty hours, Toph!" A loud argument was making its way out of the ship. Toph's doubtless impertinent answer was, thankfully, muffled by the ambient noise.
"Yes, you little dung beetle, I know why there's dirt. What I don't know is how the hell Katara didn't lay into you for trying that shit!"
"Katara was having a normal emotional reaction to her dumb-as-rocks brother disappearing in the middle of the night in along with a drysuit and packraft!" Katara, suddenly sounding more like herself, turned to shout at the duo. "Which," she said meaningfully, looking back to Sokka. "We are going to have a long talk about later."
Yue stifled what might have been a giggle behind a gloved hand. Sokka rolled his eyes at both their reactions. "Sure, sis," he replied. He did feel kind of bad about the quality of the note he left, which had in retrospect barely covered the extent of the situation at all.
"Please excuse my… directness," Katara was trying now. "I just worry about him when he's being an idiot. So rather a lot."
"Hey, Snoozles is alive too!" Toph trotted blindly in Sokka's direction and swung a high-five in the approximate area of his face. It might have worked, had there been anyone standing there. "Damn," she scowled. "I fucking hate ice."
"Toph, Princess Yue, Princess Yue, Toph," said Sokka, voice dry, catching Toph's arm to give her a point of reference.
"She's the little turd I told you about, Yue," grumbled Zuko, crossing his arms over his chest and attempting his habitual scowl. Sokka wasn't fooled.
"It's Princess Yue," hissed Katara, scandalized, and still caring more about manners than Sokka had ever witnessed in his life.
Zuko raised a lone eyebrow at her. "And I'm a prince. So we're even."
"Technically," Katara allowed.
"What's a turd?" asked Aang, a linguistic step behind. This earned him actual facepalms from his teachers and a hurried lesson on the extensive module Common Colloquialisms for Poop.
Katara, Sokka noticed, was back to trying to play above-it-all, and had taken Yue's proffered arm to go meet the combat master.
"Zuko, didn't you need to meet General Yugoda, too?" asked Sokka, loudly, before turning a toothy grin on his sister.
"Oh. Right. I do. Are you taking Aang and Toph straight to the lab, then?"
"No time like the present," Sokka shrugged.
"Okay. I'll be by as soon as I can."
"Nah, take your time," urged Sokka. Someone had to keep an eye on Katara, and Zuko at least seemed immune to Yue's feminine charms. A fact which Sokka was not going to analyze extensively, later, by himself. "I'm sure there's plenty you need to learn about. Advanced warning systems, first response protocols, you know. Battle stuff."
"All right." The look Zuko gave him was an interesting one, as if he knew Sokka was up to something but couldn't tell what. It was almost as hilarious as the terrified expression that crossed his face when Zuko noticed Katara and Yue's linked arms. Sokka nearly choked holding his laughter in as he saw Zuko hesitantly offer his arm to Katara, probably in the process of trying to desperately remember if it was some kind of expected royal etiquette. The swiftness and intensity of Katara's rejection might have pleased Sokka more yesterday, but right now the last thing he needed was for some silly infatuation to mess things up. Looking at you, Katara, he thought hard in her direction, to squash down any other thoughts that might have arisen at that. Looking at you.
Pakku took one look Aang and immediately started rubbing away a headache. Sokka suppressed the raise of a curious eyebrow. The guy hadn't even met Toph yet.
"Yes, those arrow-shaped overlays certainly resemble some of the first bio-regulatory wearable tech systems that were developed here, but I don't immediately recognize the design. Of course, this was hardly the only hub of innovation at the time, though personal shielding tech first developed here has long since become standard issue. The interface protocols are old, too, as you said to expect. Non-standard, as well, even for the time. Interesting, very interesting…" The older man wandered closer to Toph, who was standing to the side of the examination table with crossed arms and a challenging look on her face.
Suddenly, her head snapped around from where her hearing was focused on Aang, and she stared aggressively at Pakku's chest. "Excuse you, stay the fuck out of my head."
Sokka paused his speed-browsing of the engineering drawings archive and looked over. "You've got some kind of near-field communication capability, don't you?" he asked Pakku. The man's constant headaches now made a lot of sense. Sokka wondered if he had the neural processing capacity to deal with the data rate of the electronics he could communicate with.
"Yes," said Pakku, raising his hands slightly in an attempt to placate Toph. "My apologies. My mutation often triggers unpleasant anti-viral processes in more advanced cybernetics."
"Yeah, no shit, and my system doesn't appreciate you beyond exchanging network protocols, so stop whatever the hell you're doing before I make you."
"So Aang's cybernetics are one-sided, aren't they? Like Zuko's." That would explain why neither cyber-equipped boy had reacted to Pakku. On principle, Sokka thought this was a terrible idea, but on a certain level he could understand why it was done. Neural interfacing was still tricky in this day and age, let alone two hundred years ago, and it was simpler to let the cybernetics run themselves mostly independently than to enable full diagnostics and control from the host.
"What did you say about me?" asked Aang, swinging his legs over the edge of the examination table.
"Your tech," said Toph. "You can't modify what it does, but it regulates you."
"Only certain biological processes, and normally to a minimal degree that you wouldn't notice anyway," broke in Sokka, because Toph had a habit of phrasing things in the worst way possible. "Straight-up behavioral control is considered highly unethical." Even behavior reinforcement was extremely sketchy, but often deemed necessary for regulating dangerous mutations.
"The Fire Nations would seem to disagree," said Pakku, voice dry.
Sokka thought guiltily of Zuko and his strict cybernetic protocols, choosing to dwell for now on the positives: they kept Sokka and Katara safe from Zuko, and evidently they'd been enough to convince Pakku that Zuko had been telling the truth earlier. Rationally, Sokka didn't like what they implied, though. No matter how human Zuko might act, he couldn't be trusted like one. Although if anyone could out-stubborn orders written for him by someone else, it would be the Fire Prince.
"Good thing we're not in the Fire Nations, then," was all that Sokka said, in the end. He turned his attention back to Aang, who was fidgeting with a small tool he'd found lying near the exam table. "So, how should we do this? Are we going to need a wired connection to interface, or is your NFC the best option to check out Aang's tech?"
"A wired connection would be more stable and easier to sustain. Fortunately, port designs have changed very little over the years. I'll have to see if our Cache still contains the necessary drivers, though." Pakku walked out in what Sokka recognized as the absentminded haze accompanying a truly intriguing project. The guards that accompanied them stayed at the door, watching Sokka's movements but not impeding him.
Sokka left Toph to try to translate the technobabble for Aang, in favor of setting up a quick 3-D print of the connecter design he'd found in the archive. Katara would put him in the deep freeze if he pulled his screwdriver trick again, but fortunately now he had the resources that enabled him to avoid that.
"What do you mean, cybernetics control people?" Aang's normally cheerful voice now sounded upset, breaking into Sokka's concentration. Oh well, he was really just waiting for the printer to finish now anyway. "That's not right! They're only meant to help people!"
"Yeah, well, what if people want to use them to do bad shit?" challenged Toph, interspersing Creole swearwords with the formal Mandarin. "Or if their mutation makes them crazy, dangerous, or crazy dangerous? I mean, we could just let those people die."
"No you can't! The monks said -"
"Survival of the fittest, Twinkletoes. That's kind of the story of the past two centuries, except a bunch of people cheated."
"By mind-controlling other people to fight for them?"
"Technically," interrupted Sokka because he never would not. "Nothing can mind-control a person. The human brain is the original root user. So that's where insidious programming comes in. Using sympathetic logic and feedback to minimize resistance from the human brain. Making someone think the command was what they wanted to do all along, basically."
"That's bullshit," argued Toph. "I do what I want, and my cybernetics do what I fucking tell them. If I don't want to feel how cold this damned iceberg is, they won't. No matter how much they want whatever vibration profile they can infer from this stupid frozen floor to feed into my balance sensors."
"Why do you care if your cybernetic feet get cold at all? They wouldn't send any discomfort signals to your brain unless they were in danger of malfunctioning."
"That's the point," Toph continued. "I shouldn't care, but I didn't always have these feet, and I remember how much having cold toes sucks balls. So even though they're programmed to react pretty much like my bio feet did, I don't let them get cold."
"How nice for you," said Sokka. "Let's say someone decided to make them itch until you walked across a bed of hot coals though. Or even just put it into your head that doing that would feel really good. Then what?"
"I do what I want," repeated Toph, stubbornly.
Sokka was beginning to wonder if Pakku's headaches were contagious. "Anyway," he said, pointedly in Mandarin to prompt Toph to summarize the parts they'd slipped into Creole for so that Aang could follow along. "Overriding human will is a complicated topic. In theory, it can't be done purely electronically, but really anything that annoys a person for long enough will probably get them to cave. Although then this all comes back to the definition of human in the first place. Full-on cyborgs don't count of course. The question becomes, where can you draw the line? And it's kind of circular logic from there."
"Cyborgs have human brains, don't they?" asked Aang. "The monks taught that they have souls, too. So as long as there's a soul, it's a person."
Sokka sighed. "Listen, I don't know a lot about your religion, but my Islands were evangelized as fuck back in the day, and the soul is a discussion I'm not even going to start. So that's why we've got our nice metrics. Like ZHF."
"You can't put a number on humanity," said Aang, frowning. "How can one person be less human than another? That doesn't make any sense!"
"Yeah, Sokka. Explain that to little-old-cyborg-me," challenged Toph with a toothy grin.
"It's science," protested Sokka, in what was far from his most eloquent argument. The truth was, though, that he'd never had to think about this concretely before. He'd never met an actual cyborg before, and then the first one he did meet turned out to be just as human as Sokka himself, and now here was Toph, toeing the line between human and cyborg just because she'd been born sightless. "It's complicated."
"It's not so hard," said Aang. "Everyone knew this shit in the monastery. We didn't need scientists to tell us if someone was a person or not."
Sokka's argument died on the tip of his tongue because Aang couldn't have said what Sokka thought he'd just said.
"Did you just cuss, Aang?" Toph's tone was delighted. "Hell yeah! World's Greatest Language Teacher, you're looking at her."
Aang managed to look simultaneously confused and guilty. Slowly, he asked: "The word 'shit' doesn't mean what I think it means, does it?"
"Nope," cackled Toph.
Sokka took mercy on the kid and told him what Toph clearly wasn't going to. "It's yet another word that means poop. Not 'stuff', although we use it that way in slang."
"Shithead," added Toph for good measure.
Further argument was forestalled when Pakku came back into the room. "The software is ready. Try establishing the wired connection now."
"You good with that, Aang?" asked Sokka, approaching with the connector.
"Okay," Aang shrugged, doing his best not to fidget as Sokka hooked it up to one of the FlexSicon chips at the base of his spine.
A spark jumped into the dry air, barely missing Sokka's fingers. He frowned; he'd double-checked the amperage requirements, there shouldn't be a problem…
In another room, a smoke alarm began to blare.
Pakku's eyes widened. "Unplug him now!" he ordered, and Sokka hastened to comply as Pakku rushed out to see to the alarms.
"What the hell is going on?" demanded Toph. "Aang? You okay?"
"Yeah, I'm fine." The boy laughed nervously. "I guess the equipment doesn't like me."
"This makes no sense," muttered Sokka, looking at the numbers scrolling across the flickering monitor. What was even stranger than the numbers was the way computer seemed to be in trouble. Had the fire alarm come from the room that housed the computing cluster? "These numbers can't be right. Aang, your tech – do you know what it does?"
"Keeps me in one piece, mainly? Protection from the environment, like most biotech, I guess," said Aang. "I never understood the details. But everyone in the monastery had them, once you got strong enough."
"I don't think this protects you from the environment, Aang." Sokka looked him in the eye, serious. "It's designed to protect the environment from you."
Toph bristled at that, ready for a fight, but paused when looked at Aang. Sokka, too, had been watching carefully for his reaction; the boy looked strangely resigned and downcast compared to his usual cheerfulness.
"The fuck does that mean, genius?" demanded Toph, finally. "Aang wouldn't hurt a fly!"
That was true, Sokka thought, quickly running some ballpark estimates. No, Aang wouldn't hurt a fly because the biotech he wore was keeping the force of a hundred suns at bay. More than that, even. It was somewhere in between that and the point where a logarithmic scale became laughably inadequate on the axis approaching unlimited cosmic energy.
Sokka gave in and re-formed his worldview for the second time in so many days, and opened his mouth to speak a sentence that he'd never thought would leave his lips. "Aang — I think you're the Avatar."
A/N: Hee hee... and the wonderful thing about AUs is that absolutely no one is surprised about this.
I hate soulmate AUs (and de-aging/age-swap AUs) with a fiery passion, but I do recognize that having Yue and Katara as the Moon and the Ocean is basically a soulmate AU so... Feel free to roast me for being a hypocrite.