Al yawned as he pushed the cargo bay door open, stepping over the thick airtight sill and into the cavernous, dimly-lit room. It was one of the many small bays scattered across the hull of the Wind Chariot, its walls veined with thick, bolted bulkheads and skeins of ductwork.

"Good morning, Brother! Katara said you might be down here."

Ed nodded distractedly, his attention focussed on the alchemical array he was chalking onto the checkerplate flooring of the bay. He looked dishevelled, his hair still mussed from sleep. Al cast a glance over his work; the array was a simple one, designed for metallic transmutation. At its center lay a single bolt, whose colouring matched the dull metal of the airship's walls.

"Hi, Al. Just in time. I'm going to see if I can use alchemy on sky iron. Plus, any chance to use my alchemy again..."

Al came closer, hunkering down beside his brother.

"We still don't know how, why or if alchemy affects Bending, Ed. You might want to take this slowly..."

Ed gave him a disappointed glance.

"C'mon, Al. The only way we can learn exactly what that affect is is if we experiment, right? Plus, this metal... it's incredible! Here. Feel it."

He handed Al the bolt. He tried to heft it in his hands, but was surprised to discover that there was no heft to speak of. The bolt was cool, slightly rough, and definitely metallic, but...

"It's as light as wood, almost! Incredible."

Ed grinned.

"I know, right? I measured the density; it's even less than that of sodium! It floats in water! But it's hard enough to scratch carbon steel!"

Al put the bolt down, reverently.

"Amazing."

Ed was on a roll.

"It gets better! I've figured something out about this airship: it shouldn't be able to fly! All the lift is generated by hot air, but in a vessel this big..."

"It should be too heavy to fly, but it isn't, because of the sky iron!"

"Think about what Amestrian scientists could do with this metal! It would revolutionize... revolutionize everything! I mean this airship is basically what Von Junker wanted to do with aerostats!"

Al was very nearly hopping up and down with excitiement, caught in the thrill of science.

"Well, Brother, what are you waiting for! Let's do some alchemy!"

Gently moving the bolt to the center of the array, Ed rubbed his hands together, taking a few deep breaths.

"Okay. I'm gonna start with simple Comprehension. If we get that working..."

"Then onwards to Deconstruction and Reconstruction! Go!"

Ed placed his hands flat against the array, and concentrated. There was a crackle of static electricity and a dim blue glow as energy began to arc off the bolt.

"Al! Get my notebook! We've gotta write this down!"

Al scrabbled around for a pencil, scribbling rapidly as Ed rattled off a long list of figures; exact density, tensile strength, hardness, atomic composition, and many, many more. The feat would have been impossible for anyone not exposed to the Truth; it normally took many alchemists using a huge array of arrays to produce the kinds of results Ed was generating, but for one whose mind contained a complete knowledge of alchemy, it was child's play.

"Got it all, Brother! But are you all right?"

Ed nodded, speaking through clenched teeth. He was obviously having to exert a considerable amount of effort to keep the alchemical flow steady.

"I'm okay! I'm just having to make most of this up as I go along! Refining the transmutation comes later!"

The light grew brighter, and the air was filled with the harsh tang of ozone as the oxygen around them ionized. For a brief instant, the bolt began to bend and alter, but then there was a low thump, and what sounded worryingly like human screaming. The entire airship canted violently, throwing Al and Ed away from the circle. The transmutation reaction crackled into nothingness, leaving a badly twisted bolt behind. The airship slowly righted itself, but if the vibrating floor and the whooping air claxon was any indication, something had gone seriously wrong. A tinny voice came over the speaking tube.

"Alert stations! Hull breach on Deck Three! Second Lieutenant Azok to sickbay, immediately!"

Ed had to shout over the noise of the siren and the increased rumble of the engines.

"Aren't we on Deck Three?"

Al nodded, and they stumbled towards the door, feeling the airship buck and shimmy beneath them. They came out of the bay, only to be pushed aside by three uniformed crew members. They were awkwardly carrying a fourth man, his uniform burnt and twisted by some intense heat. He was mercifully silent, but his worryingly still form radiated the smell of burning human flesh. Al stifled a gag. There was a sharp crack, and the airship canted again, but further this time.

"That was close!"

Ed turned to the sound of yelling.

"Come on! I think it's coming from the engine room!"

They worked their way forwards, drawn along by an increasingly powerful breeze. Turning the hatch into the engine room, they were assaulted by a buffeting gust of icy-cold wind. The hull of the airship had been punched clean through, the jagged hole edged with twisted skeins of still-glowing metal. Several of the engineering crew were trying to get a thick canvas patch across the hole, but in vain. Where the cloth touched the metal, it burned, letting off thick clouds of smoke which were whipped away by the ferocious howling wind.

"Ed! We've got to close that hole!"

Fighting his way against the powerful wind, Al pushed forwards, stumbling over the cables and pipe work that covered the floor. The hull-sealing crew noticed them, waving them back with desperate shouts. Ed shoved the nearest one of them aside, then clapped his hands together and pressed them to the wall.

"Al! I need some help here!"

Al gave one last stumble forwards, feeling his heart pounding in his ears. The wind seemed to have stopped, but then he realized that it had merely been drowned out by the adrenaline coursing through him. He channelled the ambient energy with a quick clap of his hands, and then set to work on the sky iron hull plating. Ed was right; it was difficult. Not entirely dissimilar to transmuting metal, but close enough that he couldn't do anything instinctually. He felt the Truth begin to rise up in the back of his mind, information coursing through his brain faster than his conscious mind could process. His hair stood on end, but, blessedly, the smell of ionized air was absent, lost in the stench of the burnt metal. He felt the heat singe the palms of his hands, but persisted. The metal underneath his fingers became fluid, and then, ever so slowly, began to flow inwards, sealing the gap. With one final gasp of effort, the breach creaked shut, leaving Al and Ed gasping in the sudden silence.

"Oh dearest, say to me/ you'll let me be with you/ and dearest, say to me/ You'll let me hold you by the hand..."

Si had been trying to get the song out his head all day. Fortunately, the words were cut off by the gurgling scream of sheer mental agony that emanated from within the subconscious dredging device. The techs and various other personnel scattered around the dredging bay ignored the sound completely, used to the unfortunate side effects of the dredge. Waving to the chief psychogator, Si stepped closer to the hatch, a wave of fetid, fear-scented air waving over him as it popped open. The man strapped inside the device was slightly elderly, his skin blanched and drawn with fear. His eyes were slightly glassy, a side-effect of the hallucinogens being pumped through him, and he struggled constantly against the thick metal belts holding him in place. Si paused for a brief moment, swaying back on his heels as a complicated assembly of lenses retracted into the ceiling of the device.

"Mister... Ming, was it? Are you ready to talk? Really, I don't want to drag this out any longer than it has to. I abhor torture."

The old man shuddered, his waxy face hardening somewhat. When he spoke it was with some effort, fighting against the muscle relaxants flowing through his veins.

"The... Lotus... blooms..."

Si sighed, running a hand across his scalp.

"Mr. Ming, you're not helping. You've been hardened admirably, but giving up now will neither dishonour nor shame you or your organisation. It's in your best interests to talk. You will be well treated."

Ming spat at him, muttering a curse. His anger seemed to give him strength.

"The Lotus blooms."

Wiping the thin spittle from the breast of his uniform, Si gave another signal to the psychogator. With a whir of clockwork, the device swung shut, and a series of smallish pumps began to work across the hull.

"Miss... Lingche, was it?"

She gave a quick nod, the blank mask across her face hiding her features entirely. Her voice was low and muffled.

"He's a tough nut, sir, but we'll crack him."

"Please endeavour to do just that, miss. With expedience. There are others in need of your ministrations."

She nodded again, then turned back to her control panel. The hush of the minor psychogators and technicians scattered across the dredging bay was drowned out by the whirring of gears from the machine, and then another tortured scream. Si stepped out into the hallway, sealing the thick, soundproof door behind him. He gave another sigh, one that was considerably less self-controlled than before.

"Well, that just about ruined my afternoon."

Down the hall, a door hissed open, revealing a short, stout man, escorted by two motherly-looking medical orderlies. Though he was wobbling on shaky legs, his face was nonetheless shining with a beaming glow of joy and relief. He gave a weak nod to Si as he tottered past.

"G-general."

Si paused, taking a brief instant to remember his name.

"Qiang, was it? I assume you're all cleared."

The man nodded, some semblance of colour returning to his wide face.

"M-my mind is clean, apparently. Does t-that happen to everyone who joins the-"

"Joins us? I'm afraid so, yes. Even to me, once every month. I know it's not exactly pleasant, but it's vital."

He bowed. Qiang returned the gesture, struggling to keep upright on obviously shaky legs. Si had to credit him for his composure.

"Welcome to the Ember Group, Mr. Qiang. If there's anything I can do to facilitate your transition...?"

"Yessir. My family? My wife and son?"

"I believe they were taken in for screening at the center in Si Wong. I haven't heard anything out of the ordinary, so they're probably fine. You'll see them when the next personnel transfer comes through, in a month or two."

When he returned to his office, Si found his aide waiting for him.

"Quanli? What news?"

As Si settled into his chair, he glanced at the clipboard Quanli had handed him.

"Sir, one of the Fleet Arctic submarines has sighted the Fire Lord's airship. They've linked up with an Air Fleet Arctic battlecruiser airship."

"And they want me to authorise an attack on the Fire Lord? What's this about unusual energy surges?"

"Precisely, sir. And the Attuned benders on both the airship and the warship reported some weird chi distortions; something throwing off their bending."

"Interesting. Do we know where those two mysterious gold-haired Earthbenders are?"

It took a second for Quanli to shift thought tracks. Si knew he tended to do that to people.

"Um, no, sir. We're fairly sure they're not in the Fire Lord's palace."

"Assume they're on the airship. Tell the Fleet vessels to pursue, but not to engage the Fire Lord until he reaches the Northern Water Tribe. If possible, they are to capture these two unknowns with minimal force. Nonetheless, their lives are secondary to the death of the Fire Lord."

"And the Avatar? Intelligence from the palace is that he's on board."

"Standard procedure for dealing with young Master Aang, Quanli. The captains of the, ah yes, Dao Rei Bel and Child of Thunder know what to do."

The hallway outside the medical bay was cramped; it wasn't designed to accommodate seven people. Nonetheless, Al, Ed, Aang, Sokka, Katara, Zuko, and the captain of the airship all did their best to squish. The Captain was a large man, with a bristling walrus-like moustache. His dark complexion and deep, smoldering eyes only served to make him more intimidating. When he spoke, his voice was oddly soft and lilting.

"I must apologise for this incident, Fire Lord. I will endeavour to determine what happened to the best of my abilities."

He turned towards the Amestrians, bowing as much as the cramped hallway and his massive bulk would allow.

"My thanks to you. Had you not sealed that hull breach, we probably would have had to seal off the entire secondary engine bay."

Katara gave Ed a friendly pat on the shoulder. Unfortunately, the action entailed pushing Sokka back even further into the wall.

"Katara!"

"Thanks, you two. Your alchemy really saved the day. But Captain-"

She paused.

"I'm sorry, I never asked your name..."

The Captain nodded.

"It's Commander. Commander Brahmos, miss."

"Thank you. Commander, do you know how this happened?"

He sighed.

"Well, it's quite peculiar. Apparently Engineer Zongche was bending one of the secondary furnaces, when, or so the other engineers report, he began screaming. They saw his (heat-proof, mind you) garments catch fire, then something smoky burst from his body and punched the hole in the hull. You know about the rest."

Zuko cursed, softly.

"Did any of the engineers report anything odd when it happened? Like hallucinations, light-headedness?"

Sokka made a dismissive noise.

"Hallucinations? C'mon, Zuko. The guy just lost control of his Bending. You know it can happen."

But Brahmos was nodding.

"Come to think of it, yes, they did. It was just in passing, but one of the others said that everything went... well, the word she used was 'sharp'. Make of it what you will."

Sokka was nonplussed.

"Zuko, where are you going with this? I mean a man almost died here, and you're asking them about their weird Bending magic?"

Zuko cut him off.

"Work with me, Sokka. Ed, Al, were you doing any alchemy before the explosion?"

Ed turned to Al. There was a cautioning look in his eyes. Al knew it too. They might be on thin ice here. He wasn't sure how, or why, but it was thin ice nonetheless.

"Al..."

"Yes. Yes we were."

Zuko's face hardened.

"Every time you do alchemy, something goes wrong with somebody else's Bending."

Brahmos bristled.

"You did this? To my ship? Young man, explain yourself, or I will be forced to have you thrown in the brig."

Ed bristled in kind.

"Hey, Moustachio, watch what you're saying! We just did a little alchemy! It's your engineer's fault that this mess happened!"

"Child, you will pay for your insolence! I will not hesitate to use violence if need be, despite your small size!"

"My WHAT?"

The hatch to the sickbay opened, and everyone paused. Ever so slowly, Brahmos let Ed's feet touch the floor, releasing the front of his shirt. Ed, meanwhile, stopped trying to kick him in the groin. A young man stepped out, his willowy frame and scruffy neck-beard a harsh contrast to Brahmos. The front of his red uniform was badly stained.

"Second Lieutenant Azok! How's Zongche?"

Azok rubbed his eyes, his sleeves smearing the dots of charred skin scattered across his forehead.

"Well enough, Commander. He's got shallow surface burns across most of his upper body and torso. They'll scar, and hurt like a right bitch, but he'll live."

They had moved to the observation bubble. Brahmos, casting one last stare at Ed and Al, had returned to the bridge. Sokka, being Sokka, took the floor.

"So. Alchemy does something to Bending, if it's used in close proximity. We know the symptoms, Zuko?"

"Yeah. There's a sort of clarity, of sharpness in the air..."

Aang nodded.

"Like seeing through a lens."

Sokka, clearly ready to embark on one of his infamous 'logical lectures', began to get to his feet.

"Okay. So. Lenses. And then your bending goes all overpowered and kablooie!"

Katara shot him a piercing glare. He swallowed audibly.

"Sokka, this is serious! Don't talk about- about 'kablooie' when a man almost died!"

Sokka sighed, sitting back down.

"Sorry, Katara. But you've got to admit, this is exciting! It's something entirely new! I mean one normal Firebender suddenly had enough power to punch through the side of an airship without even trying!"

He forestalled Katara with a broad gesture that sent the back of his hand smacking into Ed's left shin. The room was more spacious than the hallway, but it wasn't exactly roomy. Sokka winced.

"Sorry, Ed. Ow. Katara, I know it was an accident. But think of what could happen if you could control it! What if we mixed alchemy with the Avatar State! Huh? Am I right?"

Ed raised a hand.

"Question! What exactly is this Avatar State? You haven't really explained it to us."

Sokka groaned.

"Oh. Riiight. Aang? You're the Avatar. You tell them."

A brief explanation later, Ed looked torn.

"What's the matter, Brother?"

"It's incredible. But horrifying. I mean, Aang, you're Gott. You can make and unmake continents! You can control everything! And if we added the power of Alchemy to the mix..."

"Ed, you can't be serious."

There was an unfamiliar expression on Ed's face, one that Al wasn't sure he had ever seen before. His brother looked determined, but at the same time... afraid?

"I wish I was. I really do. But we can't. Aang, Sokka, Zuko, Katara...We told you about Father, back in Amestris. For the briefest of moments, he became God. Fifty million people died. I cannot- I will not allow this to happen. What Alchemy has done to our homeland won't be spread to other worlds!"

There was a long, tense silence. Aang broke it, hesitantly.

"Ed and Al, when I looked inside your heads, there was something... you both called it Truth. It was- well, not evil, but still bad. And you associated it with Alchemy. What is it?"

Ed sighed.

"Attempting to perform Alchemy on a human being, that is- a creature with a soul breaks the balance that is so fundamental to Alchemy. You need to trade your life to alter the life of another. Al gave his body to bring our mother back to life. It didn't work. I gave an arm and a leg to bring Al back, trapped inside a suit of armour. If you can survive 'trading' like this, you remember what you saw. On, on the other side."

"You mean like the Spirit World? It's dangerous, but not likely to kill you..."

"Aang, this isn't a world. It's just knowledge. Well, that's not what it's like at all, but- but I don't have the words. And there's this being- it calls itself Truth. It's the guardian of that knowledge. It is Alchemy, pure and simple. To pass through the gate and live is to see and learn and understand everything there is to know about Alchemy."

"So if I'd tried to see what the Truth in your minds was..."

Al broke in.

"I'm no... well, the word in Amestrian is psychologe, but in Common you might call it a doctor of the mind... Anyways, it seems that our minds consciously suppress almost all that information. Otherwise we'd go insane from the knowledge overload. We've both technically died before, when we saw Truth. So our minds know to cope, or something. If you were to try to see the Truth... Gott, I have no idea. It would be something terrible."

Ed nodded.

"But there's something else that's been bugging me, Al. About Truth."

"I think I know what you're talking about, Brother... When we came over."

Katara leaned forwards in her seat, brushing against Aang, who blushed noticeably.

"Wait. You said that you were involved in an alchemical accident and woke up here! What aren't you telling us?"

"We... we saw Truth. Only briefly. And it- well, it looked frightened. Surprised even. It said that we weren't supposed to be there. Something about a- a 'mulitverse', whatever that means."

"Not just that, Brother. It said that if- if we die, we take everything with us."

Zuolin knew he was in no state to be driving into battle again. He winced as the shallow scars in his back and sides protested. When he'd received the Earth Ki- King Bumi's request, he'd known the old man had finally snapped. Ordering technical trials and engineering tests in the face of an unprovoked attack by an unknown enemy? Madness. He should have seen it coming a long time ago. Fortunately, he was ready to do what needed to be done.

"Everyone's formed up, Driver. Get us moving."

The L-Yi light command tank surged forwards, and the fifteen others in the squadron did the same at his signal. The entire military reserve of the Si Wong Test Area was moving. Four squadrons of 16 L-Yis each, five hundred Sandbenders, a contingent of two hundred Earthenders, and almost a thousand foot soldiers and cavalry. It wasn't a large army, by any means, but Zuolin knew that it was better armed than any force in the Earth Kingdom. The foot soldiers were followed by heavy weapon teams carrying repeating ballistae, and even the Sandbending skiffs were armed with spring-loaded grenade catapults. The L-Yi swayed beneath him, its thin treads making considerably less noise than the H-Yi had. Only three days ago, he'd been pulling himself out of the wreckage of the H-Yis, and now here he was, in charge of any armoured force that would make mincemeat of any Fire Nation armour. The light L-Yi tanks couldn't compare to the sheer bulk of the H-Yis, but their ballistae were more than powerful enough. That, and they were much, much faster.

Chiha gave a low whistle.

"They're really pulling out all the stops, aren't they sergeant?"

Oi nodded, his eye still to the telescope.

"The briefing said they wanted to test some of the prototypes, but this... It looks like they're not even bothering with the rocket artillery and the big Howling Dragons."

Their Roaring Dragon, not by any means a small vehicle, was overshadowed by the massive bulk of three Ember Group Emperor Dragon-class superheavy tanks. The gigantic multiturreted vehicles plowed through sand dunes, their wide tracks throwing up huge clouds of sand. Around them were the hexagonal shapes of the Tundra Dragon tank hunter vehicles, accompanied by a few of the Spined Dragon advanced tank hunters.

"Teke, take a look at the projectors on the Emperors and tank hunters. What d'you think those are?"

The weapons didn't come close to looking like steam projectors. They were almost delicate, thin tubes of metal connected to thick conical bases. There was a creak of hinges from the front of the tank, and Teke popped his head back inside, wiping sandy dust from his face.

"I have no idea, sarge. But I'm guessing they're a hell of a lot more deadly than they look. It's hard to get a clear view from ground level; those tracks kick up a lot of dust."

Kego turned away from the boiler, screwing the lid of the furnace shut.

"If I recall the design briefings, they're built with double-wide tracks. Good for swamps and rough terrain, but terrible for dust."

Screwing his eyes against the sunlight, Oi swept the cupola ring around to face the lead Emperor. Something caught his eye on the way, however; the horizon line was a pale brown, instead of the usual bright blue.

"Be ready to button up completely, guys. Looks like there might be a sandstorm incoming."

Chiha swore softly.

"A sandstorm? Now? I thought the Owl predicted clear weather?"

Oi shrugged, his eye still on the lens.

"Well, they're not gonna call this off for a spot of bad weather."

A blister on the top of the second turret of the lead heavy tank lit up, flickering quickly. Oi took a brief second to parse the order, and then dropped back into his seat.

"Woah! Guys, we just got the attack order. They must have damn good telescopes or something on those Emperors; I've got no idea who we're gunning for. They just said hold up, then advance on their cue."

The lighter, faster Roaring dragons of the battle group slowed collectively, creeping across the Emperor, Tundra and Spined Dragons moved into a rough wedge formation, grinding to a complete halt as their guns angled towards a distant point on the horizon. The thicker steam projectors on the Tundra vehicles were canted up to lob shells at high angles, but the pointed weapons on the larger vehicles stayed quite level.

"The big ones just got the order to open fire. That's our cue. Remember, we're going after stragglers. Let the big guns do all the-"

EEEEEEEKRAKOOOM!

The force of the volley of explosions shook the tank bodily, sending waves of sand rolling down the dunes. The line of heavy tanks had exploded into a huge cloud of pale smoke and fire, dozens of needle-thin contrails streaking off into the distance.

"What in the hell-? Oh, Agni, those are some damned powerful projectors! Full speed ahead!"

Teke rammed the throttle forwards, and the Roaring Dragon sped to join the fray. As they topped the next sand dune, Oi realized that the Emperors didn't have better telescopes- they were just taller, able to see over the low ridge that had blocked the Army of the Si Wong from view. It hadn't been a sandstorm after all; merely the dust clouds kicked up by at least fifty armoured vehicles and several high-sided sand skiffs. The entire army was in disarray.

"Go! Load and fire when ready!"

Zuolin wasn't even aware of the shot that killed him. A pointed rod of metal, no longer than a man's forearm, punched lengthwise through the tank ahead of him, reducing it in an instant to a cloud of superheated metal fragments. They, in turn, tore through the hull of his command tank, flash-vaporising everything inside. In an instant, he was burned to ash. Dozens of other rounds, fired by the massive projectors of the Emperor and Spined Dragons, began to tear methodically through the Army of the Si Wong. In an instant, hundreds were dead, and most of the armoured force was crippled. There was a long pause after the screaming devastation of the first volley. The survivors scattered. They were still running when the Roaring Dragons hit them.

Oi was in his element.

"Left fifteen! Load blasting! Fire! Teke! Hard a-right! Sandbending team!"

The tank didn't react fast enough. The sand underneath its treads rose up like water, pitching the vehicle sideways.

"Gyros!"

Oi kicked a foot lever. Deep within the bowels of the tank, several disk turbines screamed into motion as the piping around them dumped all of the engine's steam pressure into spinning a series of heavy leaden disks. The tank canted, almost overbalancing, the gyros screaming, their protesting bearings filling the hull of the vehicle with acrid smoke. Then, impossibly, it began to tilt back to level, the centripetal acceleration of the gyros counteracting the massive force of the sand. The treads hit the sand, almost gently, and the gyros slowly screamed their way to a halt.

"We're still alive! Get the pressure back up! Keep moving!"

By the end of that day, the Si Wong Test range was in a shambles. Its huge sandstone fortifications, rivalling the best in the fire Nation, were split and cracked, unable to resist the immense high-velocity shots of the Emperors. The Ember Group attack force melted back into the sands of the desert. For the briefest instant, the desert sands vibrated and shook as if possessed. Small sandslides rolled down dunes. Then all was still.

-~0X0~-

Oh, Zuolin. You lived a hero and died a virg- I mean cloud of metallic ash.

I'm not entirely sure that I'm satisfied with this chapter. I've been editing it for a few weeks now, and it just doesn't feel right. I'm not sure what it is. Pacing, maybe? Or something. If you see it, tell me. I just can't figure it out.

In response to the review by SeijuroRen : I can understand your point about the Truth, and I've tried to address it here. I had always interpreted that knowledge of alchemy as being a subconscious thing more than anything else. It's not like you have an encyclopedia in your head, it's just that your brain can parse and deal with alchemy waaaaaaay better than a normal person.

Thanks to all you fine folks who reviewed and favourited and alerted! It means a lot! As always, feel free to comment, criticize, ask questions, and engage in quibbiling debates over technological and sociopolitical trivia!

Oh, and in parting- Chapter 7 might be a bit late. It is exam time, after all... We'll see. I'm making no guarantees.