So this is actually something of an experiment of mine. I love writing, do it a lot, but I usually write comics and not stories, so describing actions isn't a strength of mine since, of course, comics are a visual medium. I'll try to do my best with it.

This first chapter jumps around, and I do apologize for that. It was mostly to establish everything; later chapters will focus much more on single plotlines or locations.

As for why I chose this story, I love Xion; she's easily my favorite character in the Kingdom Hearts series. I'm also a fan of stories that follow "what if" scenarios, and decided it's time to actually put one of my many fantasies down on (digital) paper. I hope you enjoy it.

Also, the title is a play on words with Xion's name. "Shio" is Japanese for tide, or so I'm told anyway.

Standard disclaimer goes here. The image was made by Shiroi Kamaitachi, give them a round of applause for an awesome design.

KINGDOM HEARTS

REMEMBER THE TIDES

"Is that all you've got?!"

The blonde haired youth jumped back as two massive swords swung at him. As he came down, his feet hit air… solid air. A climactic battle was occurring in the sky above Twilight Town, and no one in the world was aware.

The boy, Roxas, wore a ruined leather coat; black clothing could be seen beneath all the tears caused from this fight. Before him was a massive armored figure, hovering before the clock tower and wielding twin blades twice his own height.

Xion, Roxas mentally cried out to his best friend. I don't understand!

"Stop holding back!" She cried.

Roxas and Xion - and their third friend, Axel – had been friends for nearly a year now, but within the last few months, things had gotten out of hand. If someone had told Roxas just six months ago that he would cut off all ties with Axel and Organization XIII, or that Xion would try to kill him, he would have thought they were crazy.

But here they were.

One of Xion's blades slammed into Roxas's side, and he crashed into the barrier keeping him in the air, a pattern of connected hexagons briefly appearing to mark the barrier's location. Roxas returned to his feet, panting heavily as he held up his Keyblade, and looked at Xion's mutated form with a pained expression of sorrow and confusion. I can't keep this up much longer, but… I don't think she can either. He prepared to charge one last time, but felt himself being pulled back. Sparing a glance over his shoulder, Roxas saw a swirling pool of light.

"Get ready, Roxas!" Xion crossed her swords, and without warning all Roxas saw was light. Powerful, overwhelming, the makeshift arena was surrounded in bright golden walls and Roxas was tossed this way and that, screaming in pain. When it was all over, his back slammed onto the invisible barrier for a moment, the hexagons appearing on impact… and then, the sound of shattering glass echoed across all of Twilight Town as the barrier broke apart and Roxas fell to the ground…

x-x-x

Within a seemingly endless grey room, thirteen thrones of varying heights stood in a circle. About half of the thrones were empty. Roxas looked up at the man on the highest throne, directly across from him. On it sat Organization XIII's leader, Xemnas.

Xemnas's eyes scanned the room. "Xion has vanished again." He stated in the monotone voice he was known for. While most members of the Organization pretended to have emotions from their old lives, Xemnas made no such attempt.

Xaldin, a broad-shouldered man with dreadlocks, spoke up. "Do we know where she is?"

Xemnas spared a glance at Xaldin, then shook his head slowly. "'It,' not 'she," he said. "Xion is just a Replica...a puppet."

A blond man with a goatee – Luxord – frowned. "Puppet? Someone made her?"

Sighing, Saïx brushed a lock of blue hair out of his eyes. "Puppets generally don't make themselves." His tone was condescending and matter-of-fact, typical Saïx.

Xigbar, sitting at Xemnas's right hand, laughed as he leaned back in his seat. "The Replica Program was one of our little pet projects."

The dirty blond, Demyx, looked up at Xigbar in typical confusion and gave an exaggerated shrug. "Replica whatza?"

Xaldin huffed and looked back up at Xemnas. "Perhaps you'd care to enlighten us about this 'pet project.'"

"The goal was to duplicate the Keyblade wielder's memories, and through them, his powers-thus making them our own. Vexen oversaw the project at Castle Oblivion." Xemnas glanced briefly at Axel,who was averting his gaze,after naming the Organization's deceased scientist. "However, our efforts were severely derailed by his unexpected demise. And this particular Replica - the one we called Xion -came to form an identity of her own."

x-x-x

Darkness. A sharp pain in his back.

"…as…Ro…"

Who...?Was someone calling him?

"Roxas!" The blond boy opened his eyes to see Xion's familiar blue eyes filled with fear and worry. Tears were streaming down her face. "I'm sorry, this wasn't what I intended…" Xion shut her eyes and hugged herself as she began to cry again. "Why didn't you fight back?!"

"Fight back? How… could I fight against you, Xion?" Roxas could barely focus, but out of the corner of his eye he saw wisps of black smoke streaming into the sky. Were they coming from him?

"You were supposed to stop me! I was supposed to join with you… this wasn't what I…" Xion stopped as Roxas placed a hand to her cheek. His glove was burned off from that final attack, and Xion stopped as she felt his skin make contact.

"You are my best friend, Xion… I could never… kill you…" Roxas's hand fell, and Xion caught it. "I don't care… what they all say. You're more than just a puppet… to me…" He sighed as his vision dimmed, and the smoke rose from him more quickly. So this is what it's like to fade into darkness?Xion caught his falling hand and held it tightly, crying too much to speak. How had her plan gone so wrong? Roxas should have absorbed her, and now he was fading; now without him Sora wouldn't wake up, now…

Xion's eyes widened. Would that work?

"Why are you crying?" Roxas smiled softly and reached up, wiping at her cheek as darkness surrounded him – except for the hand Xion held, which began to glow with a soft light. "Goodbye, Xion… I'm glad I got to meet you. You're my best friend… and more than that, you're…" Roxas faded into the shadows with a smile on his face, but the glow didn't fade with him.

Xion sat there silently for a long time, no longer crying but simply coming to terms with what happened. She stared at her hands which had held Roxas's, then glanced up at the clock tower. There was a new but familiar warmth in her chest, and Xion knew what she had to do.

x-x-x

The Organization's meeting chamber was empty save for Xemnas, who sat a unmoving as always on the tallest throne. Swirls of darkness appeared on another throne and Saïx materialized, legs crossed. He looked up to Xemnas. "Roxas is no more."

Xemnas's eyes widened. If he had the capability, he'd have felt surprise then. "…Is that so? This is fascinating…" He placed a hand to his chin and gave the lightest of frowns, a habit left over from his life as a human. A long time stretched on without either saying anything, Xemnas lost in thought and Saïx patiently awaiting his orders.

"It would seem, then, that the Replica Program was not a failure after all." Xemnas returned to his usual position, hands firmly placed on the armrest. "Bring me my Keyblade wielder. Fetch me Xion."

Saïx nodded even as a dark corridor opened beneath him. "I will put Axel on it right away."

x-x-x

Rain. Why was it always raining in this place?

Black heeled boots splashed through a puddle as Xion walked through The World That Never Was. Behind her, inky black shadows with golden eyes rose up. The Heartless had found a Keybearer.

Xion entered the plaza at the base of Memory's Skyscraper. Without a doubt, the Organization knew she was there. They'd send someone – Axel, probably – after her. She'd have to make this quick.

Breaking out of her thoughts, Xion noticed the Neoshadows encircling her. She stepped back, feeling a twinge of fear. I'm… afraid? Xion placed a hand to her chest. That can't be right…Her face hardened as the Heartless approached, and Xion pulled out her Keyblade… and then another one soon after. In a flash of light, the two Kingdom Keys changed: one a bright white and one a deep black. Oathkeeper. Oblivion. Xion actually held back a surprised gasp, this was certainly not expected.

Ignoring the sudden existence of two Keyblades for now, Xion struck out at the Neoshadows; they fell incredibly easily, but they just kept coming. Sheer numbers would eventually overwhelm her. Xion jumped back, towards the skyscraper, as the claws of one of the Heartless got dangerously close to her chest. Now with distance between her and the swarm, Xion tossed Oblivion forward and it whirled through the crowd. She spun on her heel, hitting three more Neoshadows behind her with Oathkeeper before catching the returning Oblivion.

With a crack of lightning, Xion looked up and saw a familiar silver haired figure atop the skyscraper. "Aerora!" With powerful wind magic, she pushed the Heartless back, giving her some breathing room. Xion took in a deep breath and ran up the walls of the building as the man on the top leaped down. She threw Oathkeeper at him; the man caught it just as she planned. When the passed each other over the large screen, Xion glanced at him with worry, but the man's blindfolded gaze was locked on the Heartless down below.

Xion reached the roof and looked down. From this height all she could see was a spot of silver among a sea of black, but it looked like the Heartless were losing. Two's better than one, Xion decided as she dived down the building, slamming the flat of Oblivion's blade into the head of one of the Heartless. Standing back to back with the man the two of them spun their Keyblades one final time, destroying the last of the Heartless. Looking at her over his shoulder, the man jumped away to one end of the plaza, prompting Xion to do the same. Upon reaching her side, Xion removed her hood and the man's eyes widened beneath his blindfold.

"Xion?!" She gave a sad smile and dismissed Oblivion. The man didn't dismiss Oathkeeper, but shifted to a more relaxed stance, no longer looking ready for a fight. "What happened?"

"I'm sorry, Riku. I tried to return to Roxas and, through him, to Sora." Xion shook her head. "It didn't quite work out the way I had planned. Roxas is inside me now, I think." She clutched at her chest, feeling that warmth again. If she didn't know better, she'd almost swear she had a heart now.

Riku frowned looked at Oathkeeper. There was probably something symbolic in the way she had given him that Keyblade rather than Oblivion. "So what are you going to do now, Xion?" He asked without looking up from the blade.

"I don't know. I'm not actually Sora's Nobody, so I don't know if I can properly merge with him."

Riku held out his hand at Oathkeeper vanished in a flash of light. "The worlds need Sora. I think we need to give it a try, don't you?"

Hugging herself lightly, Xion gave a slow nod. "I do. I'm just… scared. Genuinely scared." She looked up to see Riku walking toward her. He put a comforting hand on her shoulder, but his face wasn't comforting to match.

"Xion," Riku sighed. "Those feelings aren't yours. You and Roxas held part of him inside you. You know as well as I do that he needs that power and those memories back." As he spoke, a corridor of darkness opened up beneath them.

"I know, Riku. But… how can I?" She shivered as the darkness wrapped around the two of them, preparing to pull them to a different world. "Just yesterday I would have willingly gone along with this, as a puppet that belongs with Sora. But now… there's a worry inside me. I can't just give myself up."

"…I'm sorry, Xion. You have to."

x-x-x

Not far away, in Organization XIII's castle, Axel leaned on a railing and stared off into the dark city down below. This area was technically named "Naught's Skyway," but he always just called it "that place with the ramps." A dark corridor opened behind him and Saïx stepped out, but Axel didn't respond.

After a few minutes of waiting, Saïx narrowed his eyes and crossed his arms. "Axel."

Axel glanced over his shoulder and feigned surprise. "Sorry, I was admiring the view." Scratching the back of his neck, Axel turned around. "What's up?"

With a hmph, Saïx looked down at the city. He knew full well Axel knew he was there and purposefully ignored him. "I have a mission for you, direct orders from Xemnas. Xion has run off once again-"

"Again?!" That got the redhead's attention. Axel suddenly stood straight. "I guess I'd better head off, then."

Saïx held out his hand and stopped the dark corridor that Axel had begun to open. "If you would let me finish. Axel, Xion has destroyed Roxas and taken his power for its own." Axel started and glared at Saïx with rage barely seen. "In other words, the Replica Project was a complete success. I must admit, I'm surprised that puppet turned out as well as it did. Be wary, Axel; Xion's power has no doubt grown after absorbing Roxas, and it will be much harder for you to bring it back." With that, and without another word, Saïx vanished, leaving Axel alone in his thoughts.

Roxas was gone?

x-x-x

The circular room's light blue walls were perfectly round and gave the impression that this place went on forever. In the center, standing among circular green patterns, was a white pod resembling a flower bud. A blond girl in a white dress and a tan man dressed in red stood facing the pod. The telltale sound of a dark corridor came from behind Naminé, and two figures in black coats appeared. Naminé smiled. "Riku! Xion! Welcome back!" Next to her, DiZ stood silent but locked eyes with Riku.

Riku, still with his hand on Xion's shoulder, nudged the girl forward and turned from DiZ to Naminé. "We had an unexpected problem, and it turns out Xion absorbed Roxas's power instead of the other way around."

"That will not do!" DiZ growled. "We required Sora's Nobody to make him whole, a Replica cannot merge with him if she was not a part of him in the first place!"

Xion looked up at DiZ, the man towering over everyone else in the room, and shook her head. "I can help to at least restore some of Sora's memories." She turned to Naminé, who gave a smile. "I… I'm scared, I have to say-" she noticed DiZ's face darken at the thought of a Nobody having emotions "-but I will do what I can. I belong with Sora."

"Naminé," DiZ sighed, "what do you believe can be done now?"

Naminé shook her head and placed a hand on the pod's glass surface. "I don't know, DiZ. I really don't. But Sora can exist without Roxas; he was able to do just that after being restored at Hollow Bastion."

"Perhaps he can exist, but he will not be able to call on his full power. This sets us back far too much." DiZ was silent in thought, and then glared down at Xion. "You will give all of yourself to him. Sora will be missing the parts of Roxas you did not absorb, but we must hope it is enough." With that he turned and left, leaving Xion, Riku and Naminé alone in the room.

"Xion, if you can give me your hand, please?" Naminé held out her left arm, her right hand firmly placed on the surface of the pod. When Xion grabbed it, Naminé began to glow softly. "I will serve as the intermediary. Please, Xion, recall all of Sora's memories and bring them to the surface. We can wake him up." Naminé spared a glance at Riku, who was walking down the hall outside. Did he not want to be there when Sora awoke?

"I think I'm ready, Naminé." She began glowing faintly, and memories boiled to the surface before vanishing; before leaving her. With her free hand, Xion clutched her chest once again. "I feel like I'm going to explode. This is real fear, isn't it?"

Naminé's eyes widened. Fear? Naminé had suspected, dealing with the deep memories within Sora's subconscious, that Roxas had gained the shattered heart Sora accepted into himself years ago. And now Xion held it? "Hold on, Xion, it's almost over…"

Xion let out a terrified scream, and began fighting against the pull of memories. She's resisting, Naminé realized, when before taking in Roxas's heart she was perfectly willing to do so. With a heart comes emotions; a fear of death, a sense of self-preservation. She doesn't want to go…

Xion broke contact with Naminé, and a burst of light exploded between the two of them. "Xion, wait!" Naminé was flung against the far wall, and when she opened her eyes after the light faded… the other girl was gone.

x-x-x

"I've got it!" Axel exclaimed, surprising Roxas and Xion next to him. The two younger members of the Organization glanced at each other for a moment, and then directed their shared gaze to Axel.

"Huh? Got what?" Roxas asked.

The redhead grinned and motioned to the ocean far off on the horizon, just barely visible from their spot on the clock tower. "Let's go to the beach next time we get a day off."

Xion tilted her head and looked out to the water herself. "The beach? Where did that come from?" Despite her confusion, the thought did excite her. Something about the ocean was familiar. It almost felt like "home."

x-x-x

Seagulls cawed out as they soared over the waves and back to the thick jungle on this small island. The sun had set, and the last few animals were returning home. The waves pushed gently against the white sand, then back out; a constant pattern in their movement.

The girl groaned and opened her eyes. The feeling of sand beneath her was familiar, but she couldn't tell why. Propping herself up on her elbows, she looked out to the black ocean and an island not too far away. The lights in that island's town were almost all out, just how late at night was it?

"Where am I?"

With a gasp, pain struck through her. She fell back onto the sand and placed hands to her head. Fragmented memories washed through her, remnants of what was left; the last thing she remembered was an explosion of light and someone calling a name: Xion. Her name?

Slowly, she stood up and looked once again to the dark water. Her black coat was flowing behind her in the sea breeze. Closing her eyes and listening to the mysteriously familiar sound of the tides, Xion's eyes widened in realization: except for those fragmented images, she couldn't remember anything.