Disclaimer: I don't own Digimon. This story originated from the BROB forum of Spacebattles, and incorporates ideas from various Spacebattles users, however I have done all the writing unless otherwise noted.
Earth, the home of humanity, is a fairly boring place, which some may even call harmless, but sometimes, the most boring of places can hold strange and wonderful secrets. Every iteration of Earth throughout the multiverse holds many secrets. Some, like the actual true recipe for coca-cola, or exactly which 11 herbs and spices make up KFC's secret seasoning, are neigh constant, however there are some Earths which are different.
Some Earths have parallel dimensions existing alongside their own. Oftentimes these dimensions are blank slates, empty, but containing vast potential. Occasionally, a few of these blank dimensions can experience bleed through from their host Earths, in the form of human dreams, beliefs and imagination, but without some form of order, these manifestations tend to be fleeting, merely existing for a few moments before fading away, leaving the parallel dimensions just as lifeless as before. But, if something were to give a background order for which those temporary manifestations of dreams to exist in, then they just might become permanent, and the lifeless dimensions might just become flourishing worlds, tied to their respective Earths.
In most cases, the background order needed is created by the humans on Earth, who, in their need to facilitate interaction with each other, devise ever more complex methods of communication, leading to the creation of data networks, oftentimes called the internet. From the internet, random bits of data occasionally made the cross through between dimensions, and being inherently orderly, provide the template upon which the manifestations of dreams could exist.
Thus, the Digital World came into existence. First, it was mostly barren, the complexity of the computers of Earth, and the primitive nature of the early networks did not provide much room for complex ideas or growth, but as computers grew more complex and networks became bigger, so too did the Digital World. Until, finally, there was enough spare data to give form to an actual being. This digital being, came into existence based on human dreams and particularly, the imagination of children. Eventually, many different forms of beings came into existence, and they called themselves Digital Monsters, or Digimon for short.
Now, while fascinating, what exactly does all this information have to do with our story, especially given that our focus is supposed to be on Earth, and not some fanciful parallel dimension populated by monsters. Well the answer to that is simple, the story about to be told is that of humanities first contact with their children, the digimon, and it how it changed the world, making it somewhat less than mostly harmless.
The park was almost empty, it was late in the day, the sun had already set, and almost everybody had already gone home, the dim streetlamps, which would normally be on were not functioning. Fortunately, most of the usual parkgoers had realized that, but there were still two people on the park's soccer field.
"Tai, don't you think it's time to go home?" Sora Takenouchi complained. She was wearing a sleeveless yellow shirt, jeans, gloves and a blue bucket hat, which combined created a tomboyish image on her. She was currently berating the other occupant of the field. "Honestly, we should have been back hours ago! Our parents must be worried sick." She noticed how the boy in front of her wasn't even looking at her, instead dribbling the soccer ball. "Tai, are you even paying attention!" She reached out and grabbed her companion.
"Wha?" Taichi 'Tai' Kamiya exclaimed startled by her action. He was wearing a blue tee-shirt, brown shorts and had a pair of goggles under his spiky brown hair. "Of course I was paying attention, Sora!" Tai protested, holding his hands in a warding position, "I'm just really worried about the big game tomorrow. Coach said that-" But he never manged to tell her exactly what their coach had told him, due to the sudden arrival of a very large, very thick fog bank.
"Huh?" Sora startled at the strange change of weather on what had previously been a cloudless evening. "What's going on, I can't see anything!"
Tai peered into the fog around the pair, scratching the top of his head. "I don't know, I don't recall the weather report mentioning anything like this!" He continued to look around, and found that he could almost make out some moving shapes in the fog. "I think I might see someone." He told Sora, "Maybe this is their idea of a practical joke."
"I don't know Tai," Sora sounded worried, "I don't know anyone who could just create a fog bank out of nowhere like this."
"Maybe it's the local skating rink?" Tai mused, still watching the moving shapes, "Some sort of advertising campaign?"
"At night, in a park with practically no one there?" Sora asked skeptically, "That's just a waste of time and effort."
"Well alright, it was a dumb idea," Tai admitted, "But-" suddenly one of the shapes he had been tracking grew larger, and it seemed like it was coming right towards them. Correction, right at Sora. "Sora! Get down!"
Ken Ichijouji sighed as he paused at the entrance to the park. It had been a long day, and he had only just gotten out of cram school, because he stayed back to get some help on specific problems which he thought he could do better on. Although, that was nothing new, he always felt that he had to do better, ever since his brother…
It was late, but he knew the way back to his family's apartment by heart, the only thing which worried him was passing through the park. Ordinarily, he wouldn't hesitate to take the shortcut, because going around the park added nearly fifteen minutes to his journey, but unlike most days the parklights were out. He vaguely recalled a notice about routine upgrades taking the system offline for a couple of days while they tested out the new computerized controls, but he had honestly forgotten about it. Otherwise he would have arranged for some other method of transportation.
He sighed again, before stepping into the park. He walked briskly along the path, trying to go as fast as he could, without risking tripping, after all, you never know what could be lurking in the darkness.
Although he was in a hurry, Ken paused as he passed the soccer field. Were those people on the field? Who would be out playing at this time of night? Seized by a sudden sense of curiosity, Ken carefully moved towards the two figures, who, based on their shadows, were probably a boy and a girl around his age.
The sudden appearance of a fog bank shocked Ken into immobilization. He had never seen fog this thick before. Where had it come from?
But before Ken do start to back away, and try to find the edge of the fogbank, he noticed multiple figures moving in the fog. He could almost swear there were dim flashes of light coming from some of them. And the movement patterns that some of them had, were strange, some would flirt back and forth, like they were hovering, others seemed more animalistic in shape.
Confused, Ken crouched down, trying to keep out of sight, but still ready to run at a moment's notice. When he suddenly noticed that one of the strange figures had left the others and was moving at high speed towards where the two kids from before had been standing. Weighing his options, Ken was about to shout out a warning, when he clearly heard, "Sora! Get Down!"