Hello, hello. I am your host, 5sidedsquare. Welcome to this hypothesis (actually, since I don't really have any kind of basis for the thought, it's more of a guess. Okay, so this is a shot in the dark, like most other fanfiction stories) of discovery. Enjoy, enjoy, and hopefully you find the idea interesting. Maybe you'll even think about it, eh?

By the way, if you've read one of my other stories, namely Sora's Aphrodisiac, and you happen to be one of the people that told me that it's a lot like that other series, Koisuru Boukun, you're absolutely right, but I hadn't read that series until it was pointed out to me. And let me tell you, I felt a mixture of pride that I'd been able to come up with a scenario that a professional had come up with, and despair that a professional had already come up with that scenario. I thought it was pretty original…I guess not… Whatever, enough of my moping.

Disclaimer: I own nothing in this story, etc., except for the situation in which the character(s) find themselves/himself/herself/whatever.

This is how it began:

Xemnas swept, for there was no other way to describe the way he moved, through the Castle That Never Was. He was troubled by his memory issues. Not the memories from his life in Radiant Garden. His memory from the time he spent there, as an apprentice of Ansem the Wise, was perfect. He could recall every detail of that point in his existence, however minor. No, he was troubled by what came before. He had this feeling that there was something important in that forgotten time, something that he had known before his apprenticeship that would serve him, but was now forgotten.

He had tried countless times to remember everything, but there was always something there, blocking him. It was almost as though there was someone that did not want him to remember.

Xemnas knew that Xigbar had some knowledge of his past, but not much. The most he could get out of the eye-patched surfer pirate was that he, Xemnas, was originally two, whatever that meant, and that he had used a keyblade, which he no longer could.

"I was just a grunt, ya know? It's not like you told me anything."

Frustrating, to say the least, though it did seem like something Xemnas would do. To add to that frustration, that thing that was always blocking his memory of his past seemed to go out of its way to somehow eradicate what Xigbar told him, over time. This required Xemnas to order the man to tell him once again, so that he could collect thoughts that he'd had the day before. Eventually, the leader of Organization XIII grew tired of the routine, and stopped bothering his eyepatched second.

Now, it was during his usual sweeping through the castle that Xemnas was struck with a thought. All right, less of a thought, and more of a feeling. It was inexplicable. That unknown thing, which held back his memories, seemed to relent slightly, as though another entity had forced it to recoil, ever so slightly. With that small retreat came a memory:

A barren wasteland, covered in jutting rock formations, and craters. Dark clouds blotted out the sky as twisters ravaged the land below. There was a portion of the world's surface that was, covered in old, broken keyblades.

The memory ended abruptly, as though tethered to a leash. Try as he might, Xemnas could not remember further. He was now fairly certain that there was a consciousness meddling with his memories. That could wait. For now, he needed to explore this place covered in keyblades.

It was unfortunate that the memory had stopped before he could learn more about the place. He knew nothing of the dangers that lurked there, but he was confident in his ability to handle it. Telling none of the other members where he was headed, as he tended to do, Xemnas created a corridor of darkness, and walked through it. He found himself on the surface of the world, atop a pillar of rock.

It was as bleak as his new memory remembered.

Xemnas wandered for a while, taking in the sight of endless rocks and dust as he searched for the graveyard like area, the one covered in keyblades, from his memory. Overall, it was a rather boring world. That is, until he reached a certain area. Something told him it was called 'The Badlands'. It seemed an apt enough name for the entire planet, to be honest.

The Badlands themselves were nothing special. At best, they were a slightly clearer area than the rest of the surface of the planet. What was in the Badlands was what was interesting.

Even from a distance, Xemnas could feel the darkness emanating from the place. Once he entered, it was pretty clear what the darkness was coming from.

There was a swirling, purple sigil floating in the air. Xemnas found himself drawn to it. As he walked closer, he could see a crest, right in the center. It seemed familiar.

"You…aren't you…? Wait…he's with you!"

Xemnas looked around for the source of the voice. He saw no one. What he did see, however, was a giant ball of darkness begin to form in front of him in midair. The sigil had disappeared.

A slightly diminutive figure appeared from the darkness. It was a balance of black and white, in color, and wore a helmet, and also what appeared to be half a corrupted hula skirt. It floated to the ground slowly.

"I feel…anger…Terra!"

The voice was coming from the figure, which materialized a keyblade. Xemnas recognized the danger just in time, materializing a barrier as the figure jumped into the air and delivered an overhead swing. It crashed into the barrier with enough force to nearly shatter it. Xemnas grunted in surprise. He formed a ball of darkness around himself, and moved away. The figure chased after him, sinking into the ground, and coming up in front of him with a burst of magic. Xemnas barely had enough time to move out of the way again.

The figure charged, leaving behind a trail of darkness that blackened Xemnas' vision. He leapt high up, just as dark jaw-like things materialized below him. Unfortunately, he was defenseless in the air. The figure caught him in a flurry of blows with the keyblade, which sent him crashing into the ground.

Again, Xemnas covered himself in a ball of darkness and moved away. The figure also covered itself with a ball of darkness, but its was laced with veins of red. Shadows of the figure began to pursue Xemnas, flying out of the red-laced ball, swinging, and then stopping as if frozen. After a few moments of this, the figure itself charged from the inside of the ball. Xemnas blocked the attack, which caused the figure to fall back a little. He then materialized his Ethereal Blades, and began to attack. He landed blow after blow, striking with both his weapons and his feet in sweeping kicks. The figure didn't take the attacks for long, however, and teleported away, only to reappear above Xemnas, and swing downward, causing ice spikes to rise from the ground where it struck.

Xemnas was flung into the air by the attack, and the figure took the chance to strike him hard, sending him flying through the air. The leader of the organization crashed through several pillars of rock before stopping. He was dazed and disoriented, and even, at least he thought, slightly disheartened by the rather one-sided battle he was participating in. It was the first emotion in a long time that he could actually say he might have felt for real. His thoughts were cut short by the figure, who teleported above him, and swung downward again.

Though he was still disoriented, Xemnas managed to get his blades in front of himself, and block the keyblade bearing down on him. The figure didn't relent, but pulled his arms up, and swung downward again, and repeated the process, hammering away at the red blades. Xemnas was unsure of how long he could keep his defense up. He even briefly wondered if he was going to die.

"Xehanort!"

The figure stopped attacking, and looked around for the source of the shout. Xemnas took the chance to slip a slight distance away. The figure was about to pursue him, when he was knocked away by an incredibly powerful blow. The figure was sent skidding across the ground. What had knocked the figure away turned towards Xemnas slowly.

It was a suit of armor, also wielding a keyblade. It seemed oddly familiar.

"Xehanort…"

It closed the distance between them alarmingly fast, and swung at Xemnas, who barely got a barrier up in time. Suddenly, the figure appeared next to the armor, and began to attack it. The armor was knocked back slightly, but responded to the attack with one of its own. The two keyblade wielders dueled for a moment, the figure drawing the armor a goodly distance away from Xemnas. As Xemnas was considering leaving the fight altogether, the figure teleported to him, and attacked. The leader of the organization blocked the attack, having anticipated that that would happen while he was stationary. He countered with an attack of his own, striking the figure with a solid blow to the stomach, which knocked it away. It barely seemed to faze the figure, however, as it resumed attacking after a quick recovery.

"Stay away!"

The armor charged in, its keyblade having turned into a whip of some sort. It grabbed the figure's leg with the whip, and threw it overhead, slingshotting it into the distance. Xemnas didn't wait for the inevitable attack, however, and swung with his blades before the armor could fully turn its attention towards him. He attacked with a mixture of weapon slashes, and roundhouse kicks, knocking it back slightly. The figure, ever tenacious, teleported next to them, and fired a burst of electrical energy. Xemnas warped away, using his ball of darkness, but the armor took the attack head on. The lightning seemed to not faze the armor at all, and he just swung at the figure, which teleported and struck from behind.

Xemnas took that opportunity to bash them both with his barrier, sending them both away. The armor recovered first, charging at him like a bull. He blocked the first strike with one of his blades, and leapt gracefully into the air, landing on the armor's shoulders before he drove the other blade straight down into the helmet. The armor didn't seem effected at all, and just threw him off. It seemed that it was empty.

Xemnas didn't have time to interpret the curiosity he had just encountered because the figure teleported again, and attacked from above. Xemnas raised his barrier, blocking the attack as the armor swung at the figure, who teleported again, a distance away, and levitated in the air. It covered itself in a pointy blue light, and charged, then turned, and then charged again, both at Xemnas and the armor. Xemnas swung with his blades, deflecting the charge before it hit him. The armor did the same, until it transformed its keyblade into a sort of drill bit, and met the charge head on. The point of the drill bit collided with the point of the light, and both were blown away.

Xemnas decided that it was time to flee. He opened a corridor of darkness, and prepared to step through it.

"I feel him!"

The figure teleported to the entrance of the corridor, ignoring Xemnas completely.

"My light…"

The figure stepped through, into the darkness. The armor, seeing that its obstacle had gone, charged straight for Xemnas.

"I'm coming for you, Xehanort!"

As if he didn't already know. Vowing to return with the other members of the organization to subdue the armor, Xemnas stepped through the door, and closed it, leaving the armor alone.

~~~Its prey no longer within its grasp, the armor knelt down, and stabbed its keyblade into the ground. There it waited for some number of years, until a spiky-haired boy came along, and it challenged him to a battle...~~~

Xemnas pursued the figure, which seemed to have forgotten that he even existed. It was intent on running through the corridor. The corridor was not a place that really had a "path". You walked through it until you reached your destination, wherever that was. It usually wasn't further than a few steps. So it perplexed Xemnas that the figure seemed to be running in a certain direction, as though deliberately avoiding exits until it found the one it wanted. At least, he was fairly certain it was looking for something specific. It was pretty clear that the figure was familiar with the use of the corridor. After all, the darkness didn't go to the figure. If anything, the darkness came from the figure.

After some amount of time, Xemnas wasn't sure how long, the darkness ended. The figure didn't stop running. Instead, it kept going, until it reached the doors to a castle. It was huge, and strangely lopsided in some places while completely sideways in others. Xemnas had had the intention of attempting to capture the figure. An odd compulsion to explore the castle overrode that intention.

The figure was straining against the door, unable to open in. Xemnas walked up to it, and together they pulled. With their combined efforts, one door opened, and the figure ran inside. Xemnas attempted to follow, but only made it one step inside the castle before the attack happened.

A strong pain lanced through Xemnas' head, and his mind began to jump around. He remembered things from his time as an apprentice: sea salt ice cream with the others, studying a heart from a particularly evil thief, creating an emblem heartless…and then he forgot. As each memory bubbled to the surface, he suddenly lost it. They flashed by, small things that led to the larger picture. With a dreadful realization, Xemnas realized that the thing that had always blocked his memories was now trying to completely destroy them, both the new and old. Something told him that whatever it was was drawing power from the castle. He needed to get out. He couldn't seem to make his feet move.

The memory of the battle that he'd just had popped up, and it was blotted from his memory, piece by piece. Then it was gone. Xemnas was exceedingly disoriented. The figure running through the corridor came next. The figure crackled, like static on a television, and vanished. All that was left was the path to the castle. Xemnas couldn't let that disappear; the compulsion wouldn't let him.

With a cry of effort, Xemnas managed to throw himself back, and out of the threshold. The attack stopped, and the pain was gone. His memories were scattered, but they immediately began to reattach themselves to other memories, creating a strange chronology of events that tied together, sometimes erroneously, in his mind. Xemnas backed away from the castle, summoned a corridor, and fled.

~~~The figure raced through the castle, not caring that the magic running through the halls was eating away at it. Its light was near. It heard a thump, and fell over. It looked back. Its leg had fallen off, and was disintegrating. It didn't care. Its light was near. It dragged itself along the halls, leaving bits of itself behind as it went. Finally, it reached a certain door. The figure was barely more than an upper chest, arms, and a head now. It touched the door.

"Ventus…"

The figure burst in a cloud as the magic in the castle destroyed the being of pure darkness...~~~

Xemnas returned to the Castle That Never Was, and immediately sent out orders for the exploration of the castle to commence. He informed Saix of the route, and hurried to the Altar of Naught so that he could think by himself. There was something else, very important. It was as though there was a place in-between that castle and this castle that he had traveled to, and he had forgotten. He briefly had a vision of a barren wasteland, but it was wavy, as though he were viewing it through water. He ground his teeth in frustration at his inability to remember. He heard a throat clearing behind him. It was Saix.

"Superior. What was this castle that you discovered called?"

Xemnas thought for a moment. He didn't think it had a name. What he did recall was how it had nearly destroyed his mind. And then his impeccable naming sense came into play, just the same as it had when he named the World That Never Was, and all its areas.

"It is called…Castle Oblivion."

Epilogue

In the realm in which Terra resided with only Master Xehanort for company, the younger man chuckled.

"To think Kingdom Hearts was, literally, right over his head too. Your efforts were wasted, Xehanort." He said.

The older man just shrugged.

"A lamentable outcome, to be sure, that he would fail to grasp what was so close. Yet, it was hardly a waste." Xehanort replied.

"What do you mean? I destroyed his memory of the place. He won't be able to find it again, and I won't let you slip another memory past me."

"I told you before that you are only one of the paths that I choose to take. The same applies here. True, if he had taken Kingdom Hearts there, in the Keyblade Graveyard, my purposes would have been fulfilled right then. However, he chose to follow Vanitas' Remnant to what he dubbed 'Castle Oblivion'.

In that place, you did manage to obliterate a myriad of his memories because your power was augmented by that of Aqua's, through the power she left behind in the castle, and by Ventus, who resides inside, though he hardly knew what he was doing, since he's comatose now. You even went so far as to destroy his recent memory of the Keyblade Graveyard. In doing so, you prevented him from spending a dangerous waste of time trying to capture your Lingering Sentiment.

Your actions have prevented a certain path from being taken, true, but you have merely pointed the way to others in the process. You've much to learn yet, boy."

Master Xehanort smiled nastily as he finished his monologue.

Terra just smiled in response.

"At least this all proved one thing, though. Together, me, Aqua and Ven are much stronger than you. When we all get back together, you won't stand a chance."

Xehanort just chuckled.

"If that time comes, then we'll see."

End…

Oh Xemnas, always so dramatic when you speak.

Now, before someone goes ballistic, and starts harping on how Xemnas is stronger than what I made him appear to be during the fight, let me point out that he's only really strong after he absorbs the remnants of the Kingdom Hearts that Ansem the Wise messed up with his machine. The Xemnas in this story hasn't yet done any absorption.

Anyway, I like reviews from my readers, so…why don't you leave a review, reader?