<Establishing neural connections.>

<Peripheral neural uplink complete.>

<Central neural uplink complete.>

<Synaptic interface status: ninety-nine point eight percent compatibility.>

The artificial female voice faded into darkness, and for a moment, nothing happened.

Then, a universe exploded into existence before his eyes.

From the darkness, the virtual space seemed to unfold like a diorama with uncountable layers. It expanded and spread all around him, filling his surroundings with a blur of colors and vague shapes. At the edges, they were rapidly collapsing again and folding in on themselves. Focusing too much on these borders while the connection was established would give anyone incapable of perceiving more than three spatial dimensions a horrific headache, so Theo tried to focus on the center, where a virtual landscape began to take shape before him.

<Consciousness connected.>

<Welcome to the Prism.>

The voice quietly chimed its greeting, as the rendering completed and he found himself in the cyberspace of Eos.

The world beyond the interface followed no rules of nature, logic or aesthetic – or at least none that a human mind could readily comprehend. But the place that Erika had brought him to looked very much like a real-world cityscape. Tall, white spires grew from the ground all around him, reaching high into the darkness above. Streams of flowing code illuminated the black sky, like rivers of starlight.

But the constructs around him were no buildings. They were data structures, comprised of ones and zeroes that the visor over his eyes rendered into a shape that his human mind could comprehend more easily. He knew such structures from his work in cybersecurity – although he preferred to see them from the outside, as raw code, when he worked on them.

He heaved a weary sigh as he took in his immediate surroundings. Erika had bypassed Synthetic System's mainframe and dropped him directly into a central virtual hub, and it was buzzing with activity. This area of virtual space, known as the Prism, was created form a network of terminals all over Eos and was just like the city itself: boldly colorful, glaringly bright, utterly chaotic, and filled to the brim with people.

Theo couldn't quite decide which of these things he hated most about it.

Colorful lines, pulsing with an inconsistent glow, ran along the ground, up and down buildings, or just hung suspended in mid-air between them. Here and there, tiny spokes protruded from them, like dendritic spines of colorful neurons. These nodes could be used to directly tap into the endless flow of information that floated through this place.

Even without accessing the nodes, there was information everywhere. Windows along the smooth walls of the buildings led to different parts of this cyberspace, as well as the Transnet that connected Eos to the cyberspaces of other colonized planets through real-time quantum entanglement communication. Most of them displayed advertisements or provided a glimpse at other, even more colorful and vibrant places. Data packages hovered through the virtual streets, like bizarrely shaped little blips that trailed behind a constantly changing stream of news headlines and advertisements.

At least in here, the brazen illumination didn't hurt his eyes quite as much, compared to the real world outside. It still pained him figuratively though, thanks to the ubiquitous clashing of lime green and cyan blue and flamingo pink and sunset orange and other unspeakable and horrifically mismatched shades. All the way into the real world, a shudder of disgust coursed through him.

The colors were most definitely the worst, he decided. It did not make him miss his color vision in the real world in the least.

The other entities that moved around him did not seem to mind. Some of them were clearly AI – they often appeared in a uniform color and shape, most of them reminiscent of real world animals or strange chimeras, some in strictly geometrical shapes of odd topologies. Others could be clearly identified as humans by the faintly glowing tags that hovered above their heads, displaying their user names. The appearance of the users varied, usually depending on the hardware they used to connect, and the time and money they were willing to invest into their virtual appearances. Consequently, the human users came in all sizes, shapes and forms. From simple and diffuse shadows to high-quality renderings of fantastic fairy-tale creatures, there was a bit of everything.

Some chose to appear the same way as their real-world selves, perhaps due to lack of creativity, perhaps out of practicality. Others preferred avatars that looked like ridiculously perfect and beautiful abstractions of real human beings, with impossible proportions and such dramatic exaggerations of otherwise attractive features that some of them looked downright frightening. They were often mockingly called valley girls and boys, because they certainly looked like they hailed from the uncanny valley.

If nothing else, cyberspace certainly had made online dating in the 26th century much more interesting.

Theo looked down at himself, and found that the interface had given him a fairly standard appearance, probably based on his real self. The interface had dressed him in black pants and a long-sleeved black shirt with holes for his thumbs. His coat had been replaced by a shorter jacket, even with a hood that he almost reflexively pulled over his head now. The interface in the Cradle must have been one of the newer and fancier ones, which were capable of recognizing some visual parameters of the user, and implemented these when rendering their virtual appearance. It had also probably used his biometrics to render this body.

A sudden realization hit him at the thought, and a sense of dread took hold of him. Slowly, he lifted his head to look at the tag that was hovering above his head.

He hadn't set a foot in cyberspace in years, for a very good reason. But his custom tag was still there. Attached to his BioID, a microchip implant that every citizen of Eos used as identification, the tag was his digital fingerprint. No matter how he accessed this space, the system would search for his BioID, and his name – albeit a fake one, in his case - would appear there as his identifier. Once created to provide him with anonymity, the name now had the potential to have quite the opposite effect.

Cursing under his breath, Theo shifted his focus back to the world outside, and stretched out his hands. His avatar in cyberspace followed his corporeal movement as he reached out and searched for the keyboard on the desk in front of him.

<Peripheral neural connection waning.>

He ignored the warning message and focused on moving his real body in the real world. He would have to be fast, Erika would probably plug in and manifest next to him within the next couple of seconds. And even if he could come up with some explanation for her, his bigger worry was that the longer he stayed here like this, the higher the chance that somebody else might find him. Somebody who would recognize that old name, that clung to his presence in this digital world like a curse and brought nothing but trouble.

The familiar feeling of a hard, physical input device underneath his fingers relaxed him somewhat. With the visor still over his eyes, he couldn't see what he was typing on the barely indented keys, but he didn't need to. Changing a tag - at least temporarily - was something he could probably do in his sleep. All he had to do was fool the interface into sending a different identifier back to the mainframe. Changing a BioID, that would have taken a lot more work. But for the time being, a quick fix was all he needed.

A few rapid key strokes later, he shifted his focus back to the vision of cyberspace before his eyes. He let his body relax to control his avatar through the plug in interface again, instead of his own body in the real world. As he looked up once more, the letters floating over his head now displayed only his real name: Theodor Lee, just another inconspicuous citizen and user. He sighed in relief, only a split second before a bright light began to shine right next to his avatar. It expanded upward and to the side until it formed a passageway, and a being stepped out of the light.

He recognized Erika right away, although she looked quite different in here, and her nametag displayed a custom username, Entropy. She was clad from head to toe in a smooth and skin tight white suit, and a matching white mask covered the upper half of her face. Its lower edge was slanted and ended in a pointy tip above her nose that reminded Theo of a bird. The mask had no eyes, but it sported three lines running horizontally across it. They emitted a faint glow in a blueish-purple color that looked a lot like what he remembered her eye color to be like. Her hair was similar to the real world too – straight, long and blond. Only in this space, it flowed behind and around her as if she was submerged in water. As she turned toward him, it dragged behind her like a weightless silken veil in slow motion.

Although he couldn't see her eyes, Theo knew that she was eyeing him up and down.

"Oh it's you!" she exclaimed in surprise after a few awkward moments of silence, "I never knew you had a custom avatar."

"Uh, what?"

"Your face? Or rather... mask?" she said, and gestured at him.

He cursed under his breath. Of course, the mask - he had completely forgotten about the stupid thing. But even if he had realized it sooner, he wouldn't have had enough time to change his appearance along with his tag.

He reflexively pulled the hood deeper over his face, but there was no way to conceal it. The mask covered his head all the way down to the neck, completely in black. The front was adorned with a white faceplate, reminiscent of an android with no eyes or mouth. It was split into four parts, so that the black fabric underneath was visible through the cracks like a big X across his face.

"When did you get that? I thought you've never been into all this cyberspace stuff?" she asked and gestured around herself.

The entities around them seemed to pay them no mind as they moved past to their destinations, but he felt his uneasiness rise. He pulled his hood deeper over his masked face.

"I... uh... I never said that," he mumbled. "I just haven't been here in a long time. And I didn't exactly miss it."

She seemed more intrigued by the mask itself than the further questions his answer probably raised. She leaned forward and peered under his hood.

"It looks... rad! Where does one get such a thing?" she asked curiously.

"That's... a long story."

He didn't want to lie to her – she didn't deserve that. But this was neither the place nor the time to tell her about how exactly he had come to acquire this custom piece of avatar modification, or rather, why he had coded that simple mod for himself, a long time ago. He cast an uneasy glance up at his name tag – it still displayed his newly faked ID, his real name, to cover up the custom ID he had given himself around the same time.

He heaved a sigh, feeling only mildly reassured.

"So, what did you want to show me?" he asked, eager to shift the topic away from his appearance, and eager to get moving away from the Prism.

To his relief, she seemed did not press the issue any further, but something about that smirk on her lips told him that he would have to expect being questioned about it again sooner or later. But for the time being, she seemed to be content that he had simply agreed to come along.

"Right. About that. It's nearby. Come on!"

She cast him a beaming smile that was just as enchanting as in the real world, and turned around. And then she darted away in a white flash.

Theo had almost forgotten what it felt like to move through cyberspace. There were numerous means and modes of transportation and travel in this space, some of them practically instantaneous, some of them only accessible to AI or those few human minds who were capable of processing more than three spatial dimensions after prolonged dwelling in cyberspaces. But one of the most thrilling ways to move around was simply to run.

There was no rushing of the wind on his skin, but there was a feeling of the datastream shifting around him, which felt oddly comparable. Perhaps because his brain decided that this was the most appropriate sensation to interpret what was happening, as they darted through the glowing virtual streets of the Prism. There was no restriction of their movement to the ground, they could have taken flight just as easily as they could walk, but Erika was staying low and so did he as he followed her.

The lights and colors of the virtual cityscape around him blurred into a rainbow stream as he sped up to keep up with her. His heartbeat picked up its pace as well – not from exhaustion but from the sheer thrill of the motion. With each pulse a surge of adrenaline flushed through his body, and in the real world, he clenched his hands on the edge of the table. He chased the white glowing light that was Erika to the outskirts of the Prism, where the virtual streets were darker and the colors more mute. She stopped as abruptly as she had moved out, and he almost dashed past her in his ecstatic rush.

They found themselves in a dark and empty part of cyberspace. The data structures were of a dark, blueish grey. Tall and narrowing like needles, they merged with the darkness of the virtual sky above. The lights of the Prism were still somewhere in the distance behind them, but around them, there was not a single AI, user or obnoxiously glowing advertisement in sight. This part of cyberspace seemed abandoned, and it felt almost eerie in its peacefulness.

"Didn't think you'd be able to keep up so easily," she noted, and cast him a grin.

Was this... a test...? He thought.

Of course he knew cyberspace better than he had initially let on, and she seemed to suspect as much by now. He wondered what she was thinking about in that moment, but he didn't dare to ask. To his relief, she turned away and pointed at a data structure nearby. It was reminiscent of a low building with a domed ceiling, with four tall spires pointing toward the virtual sky at each corner. At the front, there was a massive gateway - not just in the figurative sense. It really looked like a door - ancient, made from weathered gray wood and with dark metal handles, and absolutely enormous. He had never seen anything quite like it in the cyberspace of Eos, but of course, he couldn't tell her that if he wanted her to continue to believe that he hadn't seen much of this part of cyberspace in the first place.

"How did you find this place?" he asked her.

"That's a long story," she quoted his words back at him with a snarky tone to her voice.

He rolled his eyes, and even though she couldn't see it, she giggled.

"Perhaps we can trade stories sometime," she suggested, "But for now, let's play!"

The door had a strange quality to it. As they approached, it seemed to shrink from its massive size down to a reasonable proportion. Erika put a hand on the handle and pushed it open with surprising ease, and he followed her inside. The door disappeared behind him the moment he stepped through.

He had expected that it might lead them to another part of cyberspace, but instead, he found himself in a large room. From the corners of his eyes, he could tell that it had barely finished rendering when they had stepped through, indicating that they were the only users of this program, or whatever it was. The room was completely white and on first glance, it was filled with nothing, except for stairs.

There were stairs everywhere. Leading from the floor to platforms and levels higher up, running along the walls, back and forth and upside down, leading to the ceiling, and connecting to walkways that spanned the platforms. The longer he looked at the sight before him, the more impossible shapes he spotted. Paths were twisting and looping back in on themselves, stairways led up and down at the same time, walls were walls and yet they were the floor or the ceiling. Trying to follow a path with his gaze further than a few meters at a time sent his head spinning.

"Woah..."

He had to avert his eyes for a moment. It wasn't the same kind of pain as when he looked at colors and light in the real world, but the room upset something fundamental within him – the sheer impossibility of this place was unsettling.

"Are you okay?" Erika asked worriedly.

"Yeah... yeah, I'm fine. Just what the hell is this place?" he asked and looked up at her.

"From what I've gathered, this place is called the Cube. It's some user-created game," she explained, "It seems to be pretty old, and whoever made it seemed to have forgotten about it. I've never seen anybody in here, ever, and I've been playing it for weeks. But anyway, it's a lot of fun."

She stepped forward into the room and stretched out her hand to him with an encouraging smile. Her veil of golden hair floated around her like a cloud stirred by a gentle breeze. He stared at her for a moment, and then past her, at the impossible room, in an attempt to take it all in. His second try was more successful, in that he could endure looking at it a bit longer before the paths and stairs seemed to begin to shift and move right before his eyes. He groaned in frustration and buried his face in his hands, both in the virtual and real world.

"Ahh... perhaps I shouldn't have put is right into an advanced level. But you did seem to feel quite at ease with your avatar, so I thought..." she mumbled pensively.

"It's alright," he reassured her. On his third attempt, he tried to focus on something close by – a stairway leading up to a platform a few meters above them.

"So what's the goal?" he asked.

"To reach the end of the level," she said and pointed to the other end of the room towards another door like the one they had come in through. "So you want to give it a try?"

She cast him a beaming smile, and he nodded slowly.

There was something about this room, the sheer impossibility of its geometry, and the complexity of its design, that intrigued him deeply. He wanted to see it from within. He wanted to see what was behind that door. Most of all, he wanted to come back later and pry its code apart, bit by bit. But for now, there was still a lot he could learn just from playing by the rules of this strange and surreal little world.

"Alright, you go first! I already know this level, so I'll give you a head start," she said with a smirk.

With a sigh, he moved further forward into the white room.

The door at the other end seemed close, but he knew that even if it looked like he could simply cross the room to reach it, that would have been way too easy. He chose to learn how to maneuver this space first of all, and picked a nearby stairway at random.

He lifted his foot to place it on the first step, but the instant he shifted his weight, he felt the ground pull away from underneath him. For a split second, he was suspended in midair. The next moment, he felt the pull of gravity from an entirely different direction, and he fell. He was not surprised that the room had tricked him, but he was surprised at the harshness of doing it on his very first step. Some old and unused reflexes of his were still there though, and they awoke to help him turn his body, just in time for him to barely manage a landing on feet instead of smack down on his face.

"Nice moves!" Erika called out.

Her voice seemed to be coming from afar, and he spotted her standing on one of the walls in the distance, wearing a wide grin on her face. There was no pain to be felt in cyberspace, but he really preferred to keep his ego unbruised just as well. He cleared his throat and rolled back his shoulders, and took a look around.

"I didn't expect you to land on your feet, to be honest. You should have seen me on my first attempt," she called over, "I spent more time facedown than on my feet."

"I'm like a cat," he shouted back, "I always land on my-"

He took a step forward again, and was cut off by another sudden shift in gravity that pulled him to the side. This time, he reacted fast enough to hold on to the ledge that he had fallen from – the ledge that had, mere seconds ago, seemed like a perfectly stable path to him. He cursed under his breath and pulled himself up again. Somewhere in the distance, Erika's delighted laughter echoed through the impossible room.

"Well I'm glad one of us is having fun!" he called out in an arbitrary direction.

He found his bearings again, and spotted her as she moved along a path near the ceiling now. Her body was teetering back and forth between the pull of different gravities as she moved, but her motions were fluid and she seemed to know exactly what she was doing as she crossed a serpentine walkway by walking along it, underneath it and on its sides. It was equal parts headache inducing and fascinating to watch.

There must be some trick to it... he thought, and observed his immediate surroundings again.

But there was nothing but identical, white platforms and walkways, and countless stairs connecting them. He walked forward again hesitantly, setting one foot in front of the other with slow and careful movements. It took all his sense of balance and coordination to counteract the sudden changes in gravity, but he managed to mimic the strange mode of walking that Erika had employed, albeit it with much more arm waving and tumbling. But at least he didn't fall again. All the while, he pondered what insane kind of code could have given rise to this place.

He paused at an intersection of two paths to gather his bearings for a moment. Suddenly, a movement at the corner of his eye caught his attention. The flicker was so brief that he thought it must have been a glitch. He blinked a few times in real life to make sure his eyes were not playing a trick on him. But it was still there, hard to see at first, but easier when he moved from side to side very slowly.

Something was floating there – tiny, barely visible particles filled the room, like a faint silver haze. He stopped in his tracks for a moment at the odd mental image that it evoked. From the right angle, it looked like dust illuminated by the sunlight as it floated through the air. He wondered why he would think of this, how he even remembered what that looked like, twenty years since he had last seen real sun light.

He shook his head to clear it of the memory, and focused on the dust again. He realized now what it was: a distortion in the code at those points in space. But it wasn't a glitch – it seemed to be an integral part of the makeup of this space, although its creator had probably not intended anybody to see it. The dust followed a steady and laminar flow, and after a few tentative steps back and forth along the walkway he had confirmed his suspicion. It indicated the direction of the gravitational pull.

His lips curled upward in a smile.

There's always a trick to it, he thought, and moved forward again.

He had no clear idea where his path was leading him at first, but that didn't matter much, he simply kept on walking to practise. Soon, it became easier to spot the dust and identify the locally defined up and down, and he could quicken his pace. He crossed paths with Erika twice. Once, she passed overhead of him, walking upside down. She stopped for a moment and looked up – or down – at him with a cheeky grin on her lips. She was close enough that her long blond hair would have tickled him, if the interface could have emulated that kind of sensation.

The second time, she was on a walkway below him, and she didn't seem to take any note of him. As he watched her for a while, he realized that the way she moved through this maze was very different, more intuitive and less calculating. She set one foot in front of the other as if she had walked the path a million times, but he had gathered enough about this place to know that the arrangement of the paths was randomized. Apparently, she had simply learned to maneuver this place on instinct, instead of analyzing the flow like he did.

Theo followed her gaze as she walked on, and realized that she was about to reach the door.

"Hey," he called out to her. "Wait up!"

She looked up at him, just as he stepped up to the nearest ledge. The mask concealed her eyes, but he could imagine them widen in surprise in the real world as he took a leap. It must have looked like a leap of faith to her, but he knew very well what he was doing. He still found himself incapable of perceiving the room in its entirety, but he could use the flow of the dust and the pull of simulated gravity to reach the point where she was standing. If he could manage the landing.

He fell in one direction, and then another, and then another again. He twisted his body, trying to keep his bearings despite the shifting of the forces that pulled at him. He passed by a ledge by a hair's breath, landed on a surface, feet first, and kicked off again immediately. Then he was falling again, twisting again, until he had the right angle and the right orientation.

With a quiet thud, as if he hadn't just spent a few seconds in free fall, he landed next to Erika. Had this been the real world, his legs would be shaking at the surge of adrenaline that coursed through him. His heartbeat hammered in his chest so that he could barely hear Erika as she spoke.

"Wha- How...?" she just said.

She stared at him in utter disbelief, and he was almost tempted to tell her that he hadn't been entirely sure how this would work out until the very moment he had landed. But the look on her face was just too priceless. So he decided to leave her oblivious of his little workaround for now.

"It's your home turf, so you already have an advantage. I gotta keep my little trade secrets to keep up with you," he said and smirked at her.

"Trade secrets?" she asked skeptically.

"I mean... you know, working in cybersecurity... I know a potential exploit when I see it," he quickly said.

Generously put, that was perhaps one third of the truth, but the answer seemed to satisfy her. She shrugged and turned to the door that led into the next room.

The next level looked completely different. The overall idea of the game stayed the same – there was another set of doors at the far end. But this time, there were no paths whatsoever. The walls, floor and ceiling were pitch black and smooth, and covered with a dimly glowing pattern of even hexagons. But the dust was here too. He could see it floating in the air, and just like in the room before, its stream followed different directions all over the room.

Next to him, Erika stepped forward. Under her feet, the hexagonal tiles seemed to come to life, and a stairway rose from the floor, lifting her up further as she continued to walk. After a few steps, she turned to look back over her shoulder.

"Race to the finish?" she suggested with a lopsided smirk.

He cracked a grin himself. "Of course. I'll be waiting there."

She laughed at his audacious threat, turned back, and burst into a sprint.

They crossed the room in what was probably record time. It took him a while to interpret the flow of the dust in a way that allowed him to predict which of the tiles would move up or down, but in the end, this room was much easier than the previous one, because it wasn't filled with impossible shapes from the beginning. The black hexagonal tiles only moved and shifted only around them, rising up to float in midair, or growing into tall columns. They could form stairways and walkways, sink down to form pits, or grow into walls to block his path.

But once he had gotten used to what the dust was showing him, he quickly caught up to Erika. She maneuvered this place as if it was nothing special. It occurred to him that with her work with AIs in the Cradle, she probably spent a lot of time in cyberspace, and had gotten accustomed to it. But this space was different still – a hyperdimensional, complex puzzle, that she seemed to solve without really thinking about it. Theo knew that even if he spent hours in this place, he would probably never be able to move with that same ease. Erika moved through the game as if she understood how it worked – not on a rational and analytical level, but on a fundamental, instinctual level. Just like a human growing up on a planet with standard gravity would intuitively understand that something dropped would fall to the ground. Except that in this place, gravitational pull was subject to some invisible god's whim, and the ground shifted and moved at every corner.

They reached the next door almost at the same time, with Theo coming in slightly behind her. From there on out, the levels got increasingly complex and convoluted. In one, there was a room within the room, and the further they moved, the more rooms-in-rooms appeared, recursing further and further into infinitesimally small spaces that they could barely maneuver through in their current forms. In another, they found themselves on the inside of a hollow sphere with countless circular and spiraling pathways. The dust allowed him to discern a useful path in every level, and so he continued to race Erika through the game, until he lost track of time and count of the levels they had already passed.

At the end of a level that had held a complex network of pathways that looped back in on each other in a massive knot, they reached yet another door. But this one looked different – it wasn't gray and weathered, but looked like it was covered in a fresh coat of black paint.

"This is the last level," she announced. "Shall we go on, or stop here?"

He could hear the unspoken question between her words. She was worried for him, they had probably spent more than two hours in places with impossible shapes and bright lights. But he wasn't feeling tired and his initial headache had disappeared. And in fact, he was having fun – not that he would have admitted it.

"Why should we stop?," he asked back and cracked a grin, "Are you worried I'm gonna beat you in there too?"

"Hah! We'll see about that!" She laughed and pushed the door open.

The last room was reminiscent of the first, in that it held a complex network of interconnected white walk- and stairways. But this time, there were no walls to confine it all. Instead, the entire impossible structure seemed to hang suspended in the darkness of space. Beyond the paths, there was an open view of a black sky spangled with innumerable stars. The sight had something strangely tantalizing about it. The darkness beckoned him to come closer and dive in. It reminded him of the feeling of standing on the edge of the rooftop on the SynSys building, peering down three hundred floors at the street below. And just like that feeling, jumping past the confines of the paths inside this puzzle room struck him as an almost equally bad idea.

He followed the ubiquitous stream of dust with his gaze, and quickly realized that his intuition had been right, in this case. In some places, slipping would mean to fall all the way through, past the complex paths and walkways and all the way straight out into the darkness. A shuddered coursed through him as he realized that he had no idea what that would mean. There was no pain to be felt in cyberspace, but an avatar could get stuck, and encountering spaces that an interface wasn't capable of rendering back to an organic brain properly could be painful.

"Are you okay?" Erika's voice caused him to snap out of his thoughts.

"Yeah, I'm good," he quickly said. "Where's the goal?"

Wordlessly, she pointed at the center of the room. There, suspended in mid-air and far off from any of the paths, was another set of doors like the one they had come through.

"So...you up for it?" she asked.

He hesitated for a moment, and then nodded slowly, despite having made a disquieting observation. The particulate haze was in this room, too. But none of the streams of dust led anywhere near the door.

____
A.N.

This chapter escalated a bit... so I decided to split it. But I just have tremendous fun imagining and describing topologically challenging and geometrically impossible places :D Please let me know what you think of my description of the cyberspace of Eos! Cool and interesting or too boring and long?