Rivers of Jade and the Fall of the Sky

Knuckles leaned back against the opposite wall of the tunnel, taking in their combined work in the flickering gleam of torchlight.

At the left edge of the swirly frame Tails had insisted on drawing around the mural, several long rows of glyphs in his tidiest handwriting scrawled from top to bottom, offering a brief retelling of the events depicted. No matter when and who would look at this as historical reference in the future, they wouldn't be guessing on who was involved and what sides they'd been on.

The centre of the image was taken up by Tails' actually rather good depiction of Metal Overlord, complete with long, flailing limbs that wrapped around dark clouds, drawn by Knuckles' hand, all soft edges and swirls as he knew clouds, and some slightly out of scale airships, drawn by Tails again, in technically accurate sharp angles and straight lines. The scene was illumined by bright yellow flashes of lightening, sharp zigzag lines and star-shaped highlights, added in by Sonic, quick slashes of paint and a little more of them in number than would've been strictly necessary.

At the middle bottom of the giant drawing, the three glowing figures stood out bright and proud as the lightest part of the scene, even brighter than Sonic's overeagerly drawn lighting bolts. It made them easily the focus point, although they were much smaller than the powerful robot. Sonic had drawn himself grinning, Tails looking what was maybe supposed to look thoughtful and looked a little bit weird instead, and Knuckles had ended up with a grim scowl of sorts that was somehow oddly in character, if the Guardian was being honest.

To the far right, in the lower corner, they'd signed their names, Sonic and Tails in the lettering of the surface people, and Knuckles had opted to put both languages.

"It looks awesome."

Knuckles startled at Sonic's exclamation. It wasn't that he'd yelled or spoken particularly loudly, but it had been quiet for a long moment and the sudden words seemed to be breaking a spell.

"Absolutely! I didn't think we'd do so well!" Tails sounded happy, and when Knuckles finally turned to look, the fox was standing so close to Sonic he was almost leaning against his brother, and there were matching grins on both of their faces.

Sonic wrapped an arm around Tails, pulling him even closer, but apparently mostly to get the chance to ruffle his bangs in mock, laughing... complaint? "Oh, you unfaithful, you! Come on, with the three of us working together, how could the result be anything but the awesomest?"

Tails was laughing, trying in vain to wriggle free of Sonic's hold. "Awesome doesn't have a superlative!"

"Stop deflecting, and it totally should!" Sonic too was still laughing, but he let Tails go, only to spin round on Knuckles. "What about you? You like it, too?"

Without thinking, Knuckles' gaze flashed back to their work, still shiny and slick with the slowly drying paint.

"Oh, wow, Is that a real smile? Look, Tails, he's totally smiling!" The blue hedgehog somehow managed to sound baffled and pleased at the same time.

It was only now that his attention had been drawn to it that Knuckles realized Sonic was right, he was smiling, and it felt like he had been smiling for a while already now. "Yeah, I like it," he admitted, feeling like he ought to say something.

Looking back to his friends, he found them both still smiling, too, but at him now. Sonic had paint all over himself, even on his cheeks and behind his ears. Tails had fared slightly better, but he too had paint staining his fur up to his elbows. Knuckles found himself laughing, looked away back at the mural to stop, and it was still all shiny and it would be here long after they were gone and he'd not had to paint something alone, and suddenly there was a lump in his throat instead. He blinked, trying to catch the breath stuck somewhere behind the lump. "I-"

"Whoa whoa whoa, hey!" There was a rush of wind as Sonic moved, and then there was a hand on his shoulder, a light but unwavering weight. "No need to thank us; it was fun!" He was grinning again, head tilted in a way that usually came with a joke and tease, but his ears were curved down and back in what was closer to worry.

"Yes, it was awesome!" Tails, only slightly slower than Sonic, had appeared at Knuckles' other side.

The echidna shook his head. "But I think I do. You didn't have to come. I didn't even ask you to come. But you're still here and -" He floundered, unsure of what he even wanted to say. "I'm always... alone, here."

Sonic frowned in instant indignation. "We come visit!"

"That's not what I mean and you know it." Knuckles finally found himself able to meet the hedgehog's eyes. "I don't - I'm used to being on my own. I'm fine being on my own. It's rare that I miss having people around, because there never were, not that I remember. But this-" He waved vaguely at the new mural. "This... I - I didn't know if it would even make sense or work out or have any point if I celebrated this without, I dunno, whoever was supposed to celebrate this together. There aren't other clans or families or whatever to come visit for occasions like this. It's just- me, left."

"No, there's us left." Tails was looking up at him with bright blue eyes, narrowed in that same unwavering sense of certainty Sonic's hand still held on his shoulder.

"He's right," the hedgehog agreed. "Look, we're on a mural together. I hear those things are always right." He winked, but that didn't take the rare serious look off his face.

Knuckles nodded and swallowed the lump. "Thanks. And sorry." Embarrassment had taken a while, but now it was there and part of Knuckles wanted to duck his head and hide behind his quills.

But Sonic was smiling with a casual shrug. "No worries, people get all emotional about New Years or Christmas or whatever holiday of theirs everywhere."

"Yeah," Tails agreed, "it gets really mushy sometimes!"

Sonic pulled a face. "Like those romantic Christmas songs... Ugh."

Tails grimaced, too. "Those are the worst! Yuk!"

Knuckles laughed, and next to him, Sonic's stomach gave a loud growl that made Tails laugh along with Knuckles.

Sonic for his part grinned ruefully, claiming back his hand to pat at his belly. "Okay, now this was fun and all, but please tell me this isn't a fasting holiday and we can go grab some snacks now?"

"Didn't you eat breakfast?" At another time, Knuckles might have been annoyed, but for the moment, still faced with their mural, he felt light and carefree and like he could really accommodate Sonic's being always hungry. They had time for a snack. Still, it didn't hurt teasing him.

"That was forever ago! I'm half starved already!"

Next to Knuckles, Tails waved his hand in a so-so gesture. "Close enough."

Knuckles shook his head in exasperated amusement. "Yeah, okay, we'll find you a snack. How do you like apples? The trees in the Marble Gardens carry the first ripe ones."

Sonic grinned. "They're not chili dogs, but that sounds good."

"I'm sorry; chili dog trees don't seem to like the climate up here." Knuckles tried for an 'apologetic' shrug with it.

As hoped, it broadened Sonic's grin and pulled a giggle from Tails. "Maybe you should try a greenhouse," the fox quipped.

"Maybe next year."

"Right, best start a garden project in spring."

"Do you do lots of garden projects, Tails?" Knuckles started off down the corridor, mentally mapping out a way that would take them towards the Marble Gardens quickly and without actually passing through the deeper parts of Hydrocity. There was no need to terrify Sonic today.

"No, he builds planes in his freetime. Planes come with the advantage you don't need to remember watering them." Sonic was still grinning. Or again? It was hard to tell, because for some reason it seemed his most common facial expression.

"Hey!" Tails bristled. "I have that cactus!"

"Yes, and it's a cactus. They survive deserts."

Knuckles shook his head at the antics. "You could always plant stuff outside, you know. There's this thing called rain."

"Ohhh! Brilliant idea, don't you think, Tails?"

The fox leveled a glare at Sonic. "Yeah, quite."

Tails was good at a lot of things, pretending to be mad was not among them. Knuckles grinned to himself while he led them down a set of stairs and into another tunnel. It was narrower than the last, and the sandstone bricks that made up the walls of the more ornate tunnels higher up soon gave way to sleek, dark and mostly featureless rock.

His friends had forgotten their playful squabble and were looking around with interest. "We didn't come through here on our first visit," Sonic noticed.

Knuckles didn't bother questioning if 'visit' was the right word here. It was definitely the right word today, after all.

Tails was looking at the walls and ceiling. "Is this part of a natural cave?"

"Parts of it, I think. There are places where you can see traces of tool use, though. I think it was broadened and connected where it didn't form a full tunnel you could walk through." Knuckles swept a look along the stone walls around, too. A bit of water was dripping from one of the walls.

They met a lot more water at the next intersection where their tunnel merged with another one. The middle of the tunnel ground had turned into a swift and noisy stream that covered more than half the tunnel's width.

"Are you intending to get us a bath, Knux?" The light tone almost entirely covered any background nervousness. Sonic probably didn't have the best memories of water-filled tunnels on the island.

"No, although we could use some washing up." Knuckles tucked off his gloves and knelt to scoop up two handfuls of water to try wipe the leftover paint from his gloves and arms.

Tails followed suit, and even Sonic gathered up some water to try and wash off the abstract artwork he'd produced on himself.

Standing back up and wringing out his gloves, Knuckles' eyes followed the stream uphill. "This is rare, especially in summer," he said. "Most of the time, this is a dry tunnel. It carries more water than this in spring with the snowmelt, but rarely in summer."

Tails looked up at him from where he was by now crouched next to a protesting Sonic and trying to wipe away the paint from the hedgehog's face. "So, where does it come from then? Hold still!"

Grinning and ignoring the last part as well as Sonic's cursing as Tails continued splashing water over his head, Knuckles pulled his now mostly dry gloves back on. "There was a heavy storm last week. Lots of rain. The water eventually runs into Hydrocity and its canals, but all that surface water has to get there first. Takes time."

"I see." Tails left off the grumbling hedgehog.

"Long as we don't have to swim," Sonic mumbled, brushing a hand through damp, sleek quills.

"I don't think so. This tunnel and the next few go down almost the entire time until they reach Hydrocity. Unless you build a dam in one, the water will just flow off." Knuckles smiled. There was a fine balance between wanting to make fun of Sonic, at least a bit, and the willingness to not make his guest uncomfortable today, along with the memory of several near drowning episodes that in a way actually justified Sonic's fear.

The information seemed to pacify the hedgehog for now, though, and they continued their way, uphill now. If they walked in line, nobody had to step into the water.

"How comes these tunnels are so mundane looking and the ones we came from and some in Hydrocity are so full of wall paintings and statues and such?" Tails was looking around again, always curious.

"It's a shortcut. A utility tunnel, you could say. It's not meant to be frequently used by a lot of people."

"Hydrocity was?" Sonic frowned. "I mean, there's boats and everything, but it doesn't seem a public park."

Knuckles shrugged. "It's fundamental to the Island's continued supply with water. The old writings speak of people finding and worshipping water spirits there. There aren't murals, not painted, but gold and jewels making up pictures. There aren't many left, most have been destroyed over the centuries, but some are still there."

"Can we see one?" Tails' double namesakes trashed in excitement.

Sonic for his part looked less than awed at the idea. "Does it involve drowning?"

Knuckles grinned. "It doesn't have to. We can take a small detour down the next intersection, will take only a few minutes, then we can go back. No water, I promise. Not more than here."

Sonic nodded at that, and Knuckles picked the left turn instead of right at the next tunnel they met. It led them steep down, past two stoic looking statues of echidna warriors that Sonic flipped a grinning salute which Knuckles decided to ignore, then through a door into a wider corridor with walls made from the greenish-blue tinted bricks that were typical for Hydrocity.

The water flowed off further downhill, joining a canal running along next to this tunnel's walkway, but Knuckles followed the corridor the other way for a moment, until they stood in front of a wall that was all gold and glittering gems, carefully arranged to form a picture of water and waves and vaguely people-like shapes rising from it under a distant, misty waterfall. Turquoise, opal and jade glistered as waves and waterfalls and twinkled in tune with streaks of gold invoking the image of sunlight falling into the room depicted.

Sonic whistled through his teeth. "That sure is something."

Tails reached out a hand as if to touch it, then pulled it back. "It must be worth... I don't even know how much. What does it show?"

"I don't know." Knuckles shrugged. "A lot of writings on walls and parchment alike have faded with time, and the picture has no inscription with it. I think we're seeing water spirits rising from the depths, but if there's a story to it, I don't know it."

Tails sighed. "It's sad to know how much is lost."

It wasn't a new sentiment to Knuckles, but he didn't know what to say in return. There was nothing he could do about it anyway.

"Story or not, it's pretty epic." Sonic smiled. "It's all sparkly and shiny. To think someone went and put that on a wall down here..."

"Do you think it was made down here?" Tails was frowning. "I'm not an expert, but I imagine you need special tools and everything."

"It's possible it was made somewhere else, a forge or a workshop, and then assembled in this place. It's not a thick wall. Just a single row of bricks." Knuckles waved at the artwork. "There are maps of these tunnels, and you can walk in another tunnel to right behind this wall here. If you stand there, you can hear the water running on the other side of the wall. It's possible the bricks were decorated and then put together to form the picture in this place."

"Huh." Tails rubbed his chin. "Maybe it was a doorway once, and then someone closed it off with this?"

"Possible. Maybe it was no longer being used, or it was closed down for a reason. If we could walk through there, we could go up that way to where we'll be later."

Sonic was apparently done appreciating sparkling old walls now. He poked at an obvious hole in his stomach. "Ready here?"

Knuckles laughed. "Yeah, let's go before you starve on us."

"That's a real possibility," Sonic insisted.

"Uh-huh."

They went back up the way they'd come, and passed another intersecting tunnel on their way back uphill. The ground here was distinctively washed out; a lot more water must have gone down here earlier. Knuckles in front with Tails and Sonic trailing behind, they picked a way around the mud and loose rocks and the still rather broad stream.

Sonic was ranting about this being a terrible choice of way when he stopped mid-sentence at a weird, grinding sound from above. "Did you hear -"

He didn't finish. Suddenly there was a loud crash, like drawn out thunder, a splashing, grinding, creaking cacophony. Knuckles span round just in time to catch a look of Sonic's wide eyes, then the world around them dissolved into falling rocks.

Something hit him hard against the chest, but it was too soft and furry to be a rock. Tails! And he moved too fast to actually have moved by himself.

The force of the collision knocked the wind out of Knuckles and threw both him and Tails what seemed a good distance through the air. The echidna landed painfully on his back, with Tails somehow on top. It was instinct that made him roll over in spite of his aching limbs, shielding Tails and his own head as good as possible under his arms.

Behind and around, with deafening noise rocks slid and fell and tumbled. Knuckles reached out to the Emerald's energy in a panicked rush, and it sang through his veins just in time to make whatever hit his back right then painful but not deadly. The Guardian chocked on a gasp, scrambled for a semblance of the sense of control that was needed to make this hasty emergency grasp on the Chaos energy less dangerous than the falling rocks. It trashed and churned under his skin, reacting to the panic that had drawn it rather than the control and balance that was more the Master's nature.

Focus! Knuckles ground his teeth, eyes squeezed shut and fought to block out the noise and the impacts of rocks still falling around and on him.

Below him, Tails whimpered, and Knuckles pulled him close to his chest and the energy around them both, hanging on with a firm hold now.

Then, suddenly, it was quiet. In his grasp, the Master Emerald's energy flickered and sizzled, prickling along his back as it worked to undo whatever damage had been done. Knuckles stopped fighting it, allowed his mind to check on the link with the Emerald, and relaxed minutely when he found it safe and unharmed, only troubled by his own turmoil. They were not falling then; the Emerald hadn't been taken or worse.

"Knuckles? Knuckles!" Tails' calls pulled him back to the here and now.

"Yeah?" His voice was a rough gasp.

"Can you move? It's not that I'm not grateful, but you're heavy..."

"Oh." Carefully he let go of his friend and rolled to his back at his side. The Emerald energy was washing out to a fading tingle and he felt momentarily sore and groggy in its wake. He closed his eyes for a few deep breaths and the attempt to get a grip on himself again.

"Hey, are you injured?" Tails was leaning over him when he opened his eyes, the sudden light from of the fox's flashlight stinging sharply. The flaming torch Knuckles had carried was who knows where.

"I don't think so." Experimentally he moved to sit up. Nothing a couple rings wouldn't fix in any case. "You?"

Tails shook his head. "No. A little sore. Sonic tackled me pretty hard and -"

Sonic.

Where was Sonic?

Tails seemed to have realised he wasn't with them at this point, too. "Sonic!"

"Tails!" Sonic's voice was muffled as if distant.

"Where are you?!" Tails waved his flashlight around. The ground was stewn with rocks, and a large heap of them covered the entire height and width of the tunnel just a few meters away from them.

There came a cough before an answer. "I don't know! It's pitch dark in here. I don't see anything!"

Knuckles stiffly climbed to his feet. He had to be behind that wall of fallen rocks if he couldn't see their light. The direction of his voice fit, too.

Tails moved the shine of the flashlight across the heap of rocks that seemed to take up the entire width and height of the tunnel. There was no visible way through.

"Hey, I think I see a bit of light!" There was a trace of relief in Sonic's voice. "Just small blinks and dots, though."

"There have to be cracks and small holes in between the fallen rocks, I don't think we could hear each other if it was all solid." Tails' light still flicked back and forth across the rocks. "But it doesn't look like there's a hole big enough for one of us to crawl through. Can you come towards the light?"

"Uh, no." There was a nervous chuckle that was somewhat unlike Sonic.

Knuckles threw a worried look at Tails. "Are you hurt?!"

There was another cough and a moment of silence before Sonic answered. "No. Don't think so."

That could mean anything between the truth and Sonic bravery for "I'm quietly bleeding out while talking to you". Knuckles decided to settle on the positive option because panic wouldn't help anyone.

Sonic was still talking, too. "But I'm stuck. There's gotta be a whole heap of rocks on top of my back. I can't move."

Tails' eyes widened and Knuckles hoped that Sonic couldn't move because of the weight, and not because of some sort of spinal injury.

"Have you tried? Maybe you can push it off or wriggle out carefully."

Sonic snorted, a dull, weird sound through the wall of rocks. "I tried. The only things I can wriggle for real are my toes."

Knuckles let out a sigh, because that meant no for the worst possible injuries. "Keep trying!"

"What do you think I'll do, Knucklehead? But I'm sorry, I'm a speed and momentum guy, doing push-ups with a mountain on top is more your thing, really." It sounded like Sonic was grinning, even through the strain.

Also Tails was smiling hesitantly and somewhat disbelievingly, and Knuckles shot the fox a smile of his own, but Sonic's joking about it aside, he had a point. Sonic's strength was taken from his speed, and if he couldn't move enough to get speed of some kind, he probably wouldn't get out on his own, and not without additional injury if he'd grow desperate enough to try something like an ill-advised spin.

"Okay, don't wear yourself out. We'll try and dig through to you."

"That sounds good; you guys do the work!"

Impossible. Knuckles shook his head to himself, and focussed back on studying the cave-in before them. Boulders and smaller rocks lay chaotically toppled over one another. He set out to start at the side of a larger piece, more than halfway up to the ceiling. It would hopefully stabilise the others around it.

It was a shame he didn't carry the shovel claws, but running back to his hut for them would take far too long for his liking.

"Where do we start?"

The echidna turned back to Tails at the question and pointed. "I was thinking off to the side there. It'll be more stable than in the middle, and there's this big one that might hold some more of the weight."

Tails nodded, but still frowned. "We could use some tools..."

"We'll make do without them. I'm not bad at digging."

"Didn't say that. I'm not great a digging, I suppose. And if we're making just a small passage, we'll be in each other's way."

Knuckles contemplated the rocks. "You're not wrong there..."

Tails chewed his lip. "If you start digging, I can watch and look out for shifts. We don't need another one of us getting buried. And we can switch if you get tired."

Knuckles doubted the last part, but Tails was right on the rest, it was better to be cautious, and really, no two people could work comfortably next to each other in the narrow space.

Trying to move any of the rocks out of the way proved a near impossible task, not so much for their weight, but because the pile they had formed was terribly unstable. Everything shifted and creaked and Knuckles feared if he wasn't careful he was going to bring down what was left of the ceiling.

"I wonder how this happened," Tails said from behind him. He sounded anxious and was probably trying to distract himself.

"The rain must've washed out the ground and weakened the rocks above this tunnel," Knuckles guessed, skeptically studying the way the rocks and mud before him stapled on top of each other.

"The water!" Now Tails almost shouted, sounding alarmed enough to make Knuckles spin around to him. "Where is the water?!"

The red echidna blinked. Tails was right, there was no water on the ground here anymore, and they'd been walking next to a rather broad stream when the cave-in happened. "Oh no." He turned back to the wall of rocks. "Sonic?! Do you hear water running on your side?!"

"Yes! It sounds like a lot! Why?!" There wasn't quite as much bravado as before in the hedgehog's tone.

"Not sure, just asking!" Knuckles tried to sound unconcerned, but he wasn't sure how well he pulled it off, and as he went back to cautiously trying to shift rocks aside to make a way past them, he shifted through the tunnel layout in his head, to where slopes went down and up, trying to work out where the water would flow. If nothing else had collapsed, still the way they'd come. If something blocked that path... It would rise where Sonic was, until it could flow over the next small hill they'd come down, and flow down there, and finally gather in the tunnel behind the jewel picture, and rise to fill the tunnel from there. There wouldn't be a drain in that case.

Tails was looking at him worriedly, but didn't question the laden silence; he just took the small rocks Knuckles managed to extract and tossed them behind them. For a couple minutes, they worked quietly.

"Uh, guys!?" Now Sonic sounded closer to carefully hidden panic.

"What's it?!" Tails' eyes were wide.

"My feet are getting wet! I think - I think there's water rising in here!"

For a moment, Knuckles and Tails could only stare at each other.

Speedy's note: Honestly this entire fic was supposed to be fluff, with some angst of the "last of his kind" type. And then this happened. Oops.