A/N: If you have not already, please read Chapter 16 of Dear Sora first. It contains the prologue for this story. Thanks!

Chapter 1 – The Lost Empire

This wasn't the worst situation Riku had ever found himself in, but it was certainly up there.

"Look out!" Lea shouted, pointing at the incoming vehicles. They looked liked various kinds of sea life and glowed with a strange light. Their pilots were relentless, sending shot after shot of blue electricity at Mickey's Gummi Ship.

"I know, I know, I see it!" Riku jerked the controls to the right, and they went spinning. Lea swore as his head smacked the ceiling.

"Warn me when you're about to do that next time," he grumbled, rubbing his head and finally taking a seat. He fumbled with the seat belt and buckle for a moment before clicking them together just in time. Riku had to dive quickly to avoid the next onslaught. "Are you sure you don't want me to drive?" his backseat driver of a companion muttered.

"I know how to fly," Riku shot back. He might not be as good as Sora, but Mickey had made sure he'd learned how on their journey to save Aqua. Anyone would be struggling in a situation like this. Even Sora. Especially considering where they were. They'd gotten to the intended world, all right, but they'd warped right inside of a fight. The Heartless were all gone now, but the people that were currently attacking them didn't know that.

Lea clicked his tongue and shook his head. "Less snark, more driving, or we'll be fish food like that Heartless ship you took out back there."

Riku sighed and rolled his eyes. "Aren't there cannons or something you could be firing?"

"Can't do that, Master Riku, we're on a mission of peace."

Riku groaned. How had Kairi put up with this idiot for months? Riku was about ready to tear out his hair, and it hadn't even been three days. At every turn Lea questioned Riku's decisions and second-guessed him. But he knew that arguing with the man was pointless, so he ripped off the transmitter on his head and shoved it at him instead.

"Here, make yourself useful. Ask Tron if he can contact them somehow." Lea muttered something under his breath but did as he asked. "Mickey?" Riku called. "Any luck on the shields?"

"I've almost got them back in place," came Mickey's voice from the rear of the ship. "Sorry, Riku, but can you hang in there a little longer?"

Riku veered sharply to the right. They narrowly avoided a stream of blue lasers. "Working on it."

Lea tossed the transmitter back in his lap. "Tron suggested we show them the journal."

"Great, but how?" Riku's eyes briefly flickered to the old weather-beaten tome. It had a golden clasp that had once served as a lock, but had been broken and forcibly opened. They hadn't found Even on Radiant Garden, and it was their only clue to deciphering his research on replicas and artificial bodies. Research that they'd hoped could be used to help Roxas and Naminé.

It had seemed like the most logical next step. Ven was training with Merlin to regain his strength, and Aqua had been saved. She and Sora and Kairi had been sent after Terra, hoping to reach him in his rare moments of self-awareness, and Riku and Mickey and Lea were put on this mission.

But something had already gone wrong. Riku sighed. Of course Even's research was written in some ancient language no one could understand. Of course the only way to interpret it was to come here. And of course they were being attacked. Saving Roxas and Naminé just couldn't be easy, now could it?

"I dunno, I'm just the messenger boy," Lea drawled, breaking through his thoughts.

What was his problem? He was being uncooperative to the point it was endangering their lives. As Riku dodged the next onslaught of attacks, it dawned on him as to why that might be.

"Listen, Lea, I don't care what grudge you have against me for what I did to Roxas. You'll cooperate with us, right here, right now, or you'll lose your best shot at saving him."

Riku hated resorting to threats, but he didn't know what else to do. He stole a half second to glance at Lea, to see if his words had had their intended effect. Sure enough, Lea's eyes flashed and his jaw clenched.

"Now that's low, even for you."

Riku shoved down the urge to demand what that was supposed to mean and focused on driving. "Look, I'm sorry for what I did. I'll do whatever I can to save Roxas," well, short of hurting Sora, "but I need your help."

Lea didn't say anything. Then there was a clicking sound as he unbuckled his seatbelt and ran off to another part of the ship. A loud beeping notified Riku that one of the escape pods had been ejected.

"What's he doing?" Riku wondered. Surely he hadn't—

"The shields are back up." Mickey took Lea's now vacant seat and buckled himself in. "Where's Lea?"

They both looked out the window as the little escape pod flew past. It crashed into the water, and Lea tumbled out of it, the journal in hand. He expertly dodged the barrage of attacks aimed his way and held the journal high in the air. He was shouting something, but they couldn't make out the words.

Whatever he said, it worked. The attacks finally ceased, and Riku was able to fly the Gummi Ship to a safe landing area near the shore. They were by some ancient and great city, its massive streets and pillars peeking out from the trees stretching out before them.

When Riku and Mickey had climbed out and waded to the shore, an envoy was there to greet them. At its head were a man and a woman dressed in strange blue and gold clothing. Riku's attention was drawn to the crystals around their necks. They looked the same as the ones that had powered the ships that had attacked them. Maybe the whole city ran on the energy they provided.

"Welcome to Atlantis," the woman said. She carried herself in a regal manner, and it was clear to Riku that she was the queen. He bowed low and put his hand across his heart, and Mickey did the same.

"Your Majesty, my name is Riku. This is my friend King Mickey. We apologize for the circumstances surrounding our arrival. I assure you, we come in peace."

"Riku," the queen said. "My name is Kida, and this is my husband Milo."

Milo adjusted the glasses perched on his nose before giving them a goofy grin. He shook their hands with more enthusiasm than Riku was expecting and introduced himself.

"Gee, it sure is great to meet you. Why, I haven't seen anyone from the surface since the members of my expedition went home."

"The surface?" Riku looked to Mickey.

Milo gave them a suspicious glance. "Well, yes. That is where you're from, right?"

Well, technically, yes. Riku was from the surface, just the surface of a different world. "Um, yeah. We found something we think belongs to you."

When Lea finally stumbled on shore with the journal in tow, he showed it to Milo and Kida. Milo took it and flipped through the pages in excitement.

"W-why yes! This is the Shepherd's Journal. I thought it had been lost for good. It includes valuable information about Atlantis."

They continued on to the palace, and Riku took it all in. Stone buildings peppered a lush jungle, the sea breeze gentle on his skin. Some of the buildings were in ruins, but others had scaffolding all over them and workers smoothing the stone, repainting it and clearing away vines. And a few still yet had been restored to their former glory. They strolled through a marketplace filled with food stalls and goods of all different kinds – plump fruit, colorful sea life, exotic looking herbs, dishes painted with blue and gold spirals, baskets – the place was bustling with life.

The people bowed their heads in respect as Kida and Milo strolled by but stole curious glances at Riku and Mickey and Lea. The adults were subtle about it, but the children just outright stared at them. Riku's eyes met a small girl's, and her mother chided her. But Riku just smiled and waved, and the girl waved shyly back, her mother giving him a grateful look.

At long last their little caravan reached the palace. It was also under renovation, its great stone columns being repainted and new masonry being carried in to replace the broken stones. Pools filled with water lilies lined the great hallway they found themselves in, and Riku was struck by how beautiful this place was. It was truly a work of art, and he wondered what it must have looked like in its prime, and what had caused it to fall into disrepair to the extent it needed renovating on this scale.

Kida cleared her throat and thanked them for finding the Shepherd's Journal. She offered a reward for its safe return, but they declined.

"Actually, though, we were hoping you might be able to help us with somethin'," Mickey said.

"You can read Atlantean, right?" Riku asked.

"Well, yes. I'm a linguist," Milo said. "I've spent my whole life studying dead languages. And even a few living ones." He grinned at Kida, who smiled back, sharing some inside joke that only the two of them could understand.

"Good. Listen, can you read what this says?" Lea practically shoved the data Tron had sent containing the files with all of Even's research in Milo's face. Milo adjusted his glasses again and peered at it, commenting on how unusual the device was before reading out a few lines.

"Bodies… can be make… no, made… from data? Huh, that's odd. Anyway, continuing on. The necessary… components? Materials? Yes, the necessary materials… uh, biological…" Milo squinted as he tried to parse the next string of words. "Sorry, I'm gonna need more time to translate all this."

Well, at least we found someone who can read it.

"How long do you think it'll take?" Lea asked.

"A week or two, maybe more. My duties as king mean I don't have as much time for my studies anymore." He gestured to the splendid city around them. "As you can see, we've been rebuilding. Making a lot of good progress, too." He sighed and readjusted his glasses. "Until those strange enemies showed up, that is. I've never seen anything like them, and the Shepherd's Journal doesn't mention them, either. Kida's lived for thousands of years, and she's never even heard of them before."

Thousands of years? Did Atlanteans normally live that long? Before Riku could ask, Kida cleared her throat. "If you will be staying with us while Milo translates the book for you, there is a favor we have to ask of you as well."

"Ask away," Riku said. It was the least they could do.

"We need your help defending our city and our people. In times of great danger, the Heart of Atlantis chooses a royal host. As I am the last remaining member of the royal family with Atlantean blood flowing through my veins, it will choose me."

"Well, that doesn't sound too bad. You probably get some cool powers, right?" Lea said. "Sounds like you can probably handle things pretty well on your own."

"If Kida remains bonded to the crystal for too long, we'll lose her forever." Milo's voice was low, a grim expression on his face. "We'd prefer not to let that happen. We've locked it away for now, but if the threat gets bad enough—"

"If we can stop the threat before it reaches that point, then it will not." Kida smiled at her husband and gave his arm a squeeze, but he just looked at her in concern.

"You said there's a Heart of Atlantis, right?" Mickey asked. He and Riku exchanged looks. The Heart of Atlantis sounded like the heart of the world. No wonder the Heartless were after it. "Gosh, we think we know what the problem is," Mickey continued. "Those enemies are called Heartless, and that's probably what they're after."

He explained what the Heartless were and how they could be defeated. Milo and Kida listened intently. They both asked many questions, which Mickey and Riku did their best to answer. The Keyblade in particular was of great interest to them. Lea, on the other hand, wore a bored expression on his face and kept tapping his foot. Riku was about ready to chew him out for being rude, only for the irony of the situation to fully hit him. Sora was always complaining about how rude Riku was, and oh how the tables had turned.

Guess that's what I get for trying to be the responsible one.

Eventually, Milo and Kida showed their guests to their chambers before returning to the palace. When Kida returned, it was to inform them that Milo had started work on the translations. She had changed clothes and was now dressed in battle attire, wearing blue and gold armor and gauntlets engraved with Atlantean script.

"More of the those Heartless creatures have been seen. We must work quickly to protect the city," she said.

Well, time to fulfill their end of the deal. Riku summoned his Keyblade and followed after her.

"No, no, you have to turn the crystal one quarter back while your hand is on the inscription pad. Here, like this."

Kida put her hand on Mickey's inscription pad and turned the crystal. The pad glowed with a blue light, and the fishlike speeder Kida had informed them was called a Ketak sputtered to life. Mickey yelped and jumped on the back of the hovering craft just in time.

"Okay, so far so good. Now what do I do to AAHHHH!" Mickey's Ketak took off, leaving a jet of water in its wake as Mickey's voice echoed into the distance. Kida shook her head and smiled.

"He will figure it out in time. Riku, it is your turn."

The process went much more smoothly for Riku. Partly because he'd just witnessed Mickey's misadventures, but also partly because this wasn't his first time to drive something like this. His time in the Grid had prepared him well. Figuring out the weapons was trickier, but controlling the Ketak itself wasn't difficult. Once Lea had his ride, the three of them took off in the direction Mickey had disappeared to.

"So, Kida," Riku began. He had to shout for his voice to be heard over the rushing of the wind and the noise the Ketaks made. They were gliding low over the water that surrounded the city, heading to the outskirts where the latest Heartless attack had been reported.

"Yes?"

"Do these crystals power everything in your city?"

"Yes. They are a gift from the Heart of Atlantis. We lost much of our knowledge after the Mehbelmok… what was it Milo called it? Ah yes, the Great Flood. But then Milo came and brought the knowledge back to us. He knew how to read our language even though we had forgotten. With his help, we rediscovered how to use our lost technology. It has been useful in defending our city."

There it was again. The Heart of Atlantis. Riku was about to ask her more about it when Lea's shout drew his attention. There was a group of Heartless nearby. He summoned his Keyblade and attacked. It connected with one of them, a strange, marine-looking creature with gears and metal dotting its body. It almost blended in with their Ketaks, but its yellow eyes gave it away. Riku steered his Ketak in a loop and doubled back for another attack.

Kida, meanwhile, had vaulted off of her Ketak and landed on one of the Heartless's backs. She stabbed it over and over again with the spear in her hand till it was defeated, then used the spear to vault to the next opponent. Riku was impressed. The woman was fearless, fearless and ruthless. She could probably handle this on her own if she wanted to.

Lea was holding his own, too. Flames soon lit up the area as he hit Heartless after Heartless with his signature magic, finishing them off with lots of Fire Raids. The battle was going well, really, until an enormous Heartless Riku had never seen before emerged from the water.

"Lea, look out!" Riku lunged at Lea to try to get him out of the way in time, but it was too late. The Heartless swiped at him with its enormous claws, sending him flying off his Ketak and plunging into the water. Riku splashed to Lea's side, only for Kida to stop him.

"You deal with that, I will take care of him!" she shouted. Riku didn't argue. He froze the water around him and climbed on top of it, then launched wave after wave of powerful magic at their foe. This was followed up with a blurry of physical attacks. At some point Mickey found him and joined in. But this Heartless was fast, and by the time the two of them had finally subdued it, Riku had a few injuries of his own. Once they'd confirmed the area was clear, they made their way over to Kida and Lea.

"Riku, you are injured. Here, let me help." Kida waded through the water to him. She took the crystal around her neck and held it close to Riku's arm. Then she pressed her hand against the wound. Riku watched in fascination as a strange energy emanated from it and repaired the torn skin.

"So your crystals can heal injuries?" Riku asked, testing the arm to make sure everything was back to normal. Kida frowned and grabbed a hold of his wrist. She studied the bandage wrapped around it, including Kairi's drawing and message.

"This did not heal properly. Here, allow me—"

Riku pulled away from her and rubbed his wrist. It still gave him strange pains from time to time, but it didn't feel right to fix it. It was a testament to the lengths he'd gone to in order to save Sora, and he didn't want to lose the reminder. It was twisted, he knew, but it was his fault Sora had become a Heartless in the first place. He couldn't let something like that happen again. And it seemed disrespectful to Roxas to heal the injury like it had never happened.

Kida gave him a curious look. "You do not wish for it to be healed, do you?"

"No," Riku finally admitted.

"But surely a great warrior like yourself wants to be in top fighting form?"

"Did you hear that?" Lea said, a smirk forming on his face. "She thinks you're a great warrior."

Riku ignored Lea's commentary. "I do, but there's something I can't ever let myself forget. It's okay, I've gotten used to fighting like this."

"I understand." There was a deep sadness in Kida's eyes as she told them where they were going next. Riku wondered what tragedy had befallen her, then remembered that she was the last member of the royal family. Whatever it had been, it had taken her mother and father from her. Maybe even her brothers and sisters, too, if she'd had them. Riku couldn't help but be drawn to her. She was one of those rare people who just understood without having to be told, and the thought of saying goodbye was more painful than he was expecting.

But he pushed those thoughts aside and focused on fighting, just like he always did.

A/N: First of all, a big shoutout to my beta FlowerLady-Aerith for all of her help with this story, and a big thank you to all of my readers!

This story is the sequel to Dear Sora. It's looking like it'll be around 37-39 chapters with an overall word count of somewhere between 160,000-170,000 words.

Updates are every Friday unless otherwise noted in my author's notes, and I'm planning on having the entire story posted before KH3 comes out.

A few quick notes on content. This story is going to be darker than Dear Sora, and I will include a warning if a particular chapter has dark, heavy, or more violent material than the rest of the fic. Sora/Kairi is the main pairing, but there will be a couple of other pairings. If you're worried about one you don't like showing up, shoot me a PM and I'll let you know if it'll be in the story.

As always, thank you for reading!