1. Worlds Collide

Dr. Eggman paced back and forth in his latest fortress. After a time, he had decided to return to his world domination schemes...but he found himself at a bit of a loss. He'd puttered around a bit, building a few new robot designs...but he didn't have any ideas. "How am I supposed to defeat Sonic?" he suddenly demanded in exasperation. "I've tried any number of times, and every one has failed! I need something new...but what?" He flopped into his chair, staring at the control panels. "This is why I took such a long break...I'm out of new ideas..."

"I may have a suggestion, Doctor," a diffident robotic voice said from nearby.

Dr. Eggman turned. "Ah, Yesbot," he said, greeting the robot that came in. It was roughly eggshaped with a bobblehead that would only bounce up and down. It wasn't built for combat, but was very sturdy. He'd built it to agree with everything he said and to take abuse when he felt the need to hit something...at least, that's what the blueprints said. He couldn't quite remember building this one...but that was nothing new. He built a lot of bots, and not all of them by hand, and on occasion a few showed up he didn't remember building. These tended to be his greatest creations. He figured his subconcious mind sometimes built robots while he was asleep. "You have a suggestion?"

"I took the liberty of reveiwing your records of your battles with Sonic the Hedgehog, and I believe I have come across something that may be useful." Yesbot hooked himself to the control panel, and video started playing. "This is the battles where you came closest to visctory against Sonic the Hedgehog...and it seems it was through the use of a robot termed...Metal Sonic."

Dr. Eggman shook his head. "No, I won't use Metal Sonic again. He's far too dangerous, and I don't have complete control of him."

"Yes sir, but that's not the point." Yesbot pulled up the specs. "Your success came from using an opponent who could match Sonic in his strongest attribute...his speed. Logic, therefor, dictates that you utilize an opponent for Sonic who can match his speed...and one who would have every reason to remain loyal to you."

Eggman nodded. "I see...but how? I can't use a robot. The level of processing power required to handle traveling at such high speeds neccesitates a personality program to handle situations not included in base programing, and that's what went wrong with Metal Sonic: he became so obsessed with defeating Sonic he rebelled against me."

"Indeed...and that obsession destroyed him. You need one for whom defeating Sonic would be a means...not an end." Yesbot pulled up more blueprints. "Some time back, you built a device that allowed you to reach the world inhabited by your counterpart, Eggman Nega. By reveiwing the blueprints, I have discovered that it can be used to access other dimensions, as well. And...I have found a world that has just such an individual." On another screen, images of this other world appeared.

Eggman examined the image. "Hmm...this world seems rather peaceful..." A rainbow colored blur sped across the screen. "What was that?"

The screen paused and shifted over to the front of the blur. Zooming in, it showed the creature that was the source of the blur. "Does the specimen meet your approval, Dr. Eggman?"

"Hmm...blue..." Eggman rubbed his chin. "Blue has generally been bad luck for me...but this one just might be useful...but are you sure we'll be able to manipulate..." He took a closer look. "...her?"

Yesbot nodded. "Of course, sir. After all...you will be her only way home."


In the skies over Ponyville, Rainbow Dash continued to practice her flying, zipping back and forth amongst the clouds. Down below, she saw Fluttershy waving to her, and swooped down to her. "Hey Fluttershy! What's up?" Glancing over, she saw three smaller ponies with her. "Sweetie Belle! Scootaloo! Apple Bloom! What brings you all here?"

Fluttershy smiled. "I was just telling them about how you used the Sonic Rainboom to save Rarrity and the Wonderbolts at the young fliers competition a while back. They really enjoyed the story."

Apple Bloom bounced happily. "Can you show us the Sonic Rainboom? Huh? Huh? Please, Rainbow Dash?" The other two added their pleading to hers.

Rainbow Dash grinned. "Sure thing, fillies. Just let me get some altitude." She spread her wings, chuckling. She was never averse to showing off, and she was more confident now that she'd achieved it a second time. Flying up to a high altitude, she glanced down. "Here I come!" she shouted, and dove.

As she picked up speed, the arc of light appeared in front of her. This was the first step to creating the Sonic Rainboom, as she approached the speed barrier that few ponies could breach. As the arc began to approach a point, she grinned. This was getting easier every time.

Suddenly, down near the ground, a strange light distortion appeared. "What the?" Rainbow Dash tried to alter her flight path, but at this point she had to much momentum, and the distortion seemed to be pulling her in. As she reached the speed that would have triggered the Sonic Rainboom, she entered the distortion and her world went white.

Down below, Fluttershy gasped as it seemed to her that Rainbow Dash had dissapeared into thin air in a flash of light just before she would have achieved the Sonic Rainboom. Sweetie Belle looked up at her. "Was that the Sonic Rainboom?" she asked, confused.

Fluttershy shook her head. "No, it wasn't." She turned towards town. "Come on, we need to get Twilight Sparkle."


Rainbow Dash groaned as she came back to herself. Her entire body was sore, and her head pounded. She could also hear voices, just barely, and shook her head to clear it.

"Why did her body change so much?" This voice was angry, masculine.

"Perhaps the physics of the two worlds are too different." This voice was high pitched, lacking enunciation. "The portal device is designed for passing between worlds safely: perhaps it altered her body to be able to function here."

"Hmm...we'll figure that out later. Is she still capable of what we need?"

"Only one way to find out, Dr. Eggman. Shall I attatch the nueral manipulator?"

"Yes. Do it."

Her eyes flew open. She saw a strangely configured, shiny creature leaning over her, something menacing in its hand. She reacted, spinning her body to lash out with her hind legs, striking it hard in the chest and sending it flying back. Leaping to her hooves, she lunged for a nearby window she saw, diving out and spreading her wings, flying fast and hard for all she was worth.

After a time of flying, she came down next to a lake. Her body felt strange, and she wanted to figure out why. "I don't know what those...creatures were talking about, but..." She looked at her reflection...then gasped, falling back. She hadn't recognized the creature in the water. She took another look.

Her skin was the same color...but her face was flatter, her nose and mouth seperate protrubances now. The rest of her face seemed the same, but it wasn't just her face that had changed. Her mane was much longer, and only grew out of the back of her head instead of going a distance down her back. Reaching up to touch her changed face, she was shocked to find fingers and a hand where her front hoof should have been. Looking down, she also saw two strange lumps between her arms, starting a samll ways below her shoulders. When she moved her torso, they shook. Glancing down further, she saw that the shape of her hindquarters had changed somewhat as well, and her back knee joint now bent the other way. Her cutie mark was in the same place, unchanged, and her hind hooves were the same shape. Her tail was also as long and colorful as ever. Her wings were also much bigger.

"What...what's happened to me?" she asked in shock, staring at her reflection.

"Excuse me," a small voice said from nearby.

"GYAH!" Rainbow Dash leapt to her hind hooves, grabbing a large stick from nearby, swinging it warningly the way she'd sometimes seen Spike wave a club. She looked around for the source of the voice...and her eyes fell on an overlarge rabbit in a dress.

"Are you alright?" the rabbit asked her. "You seem disoriented." The rabbit's voice was pleasent, young and high pitched, definately femenine. This was a child, a little girl...a filly, even though she wasn't a pony.

Rainbow Dash relaxed, leaning on her club. "I am, actually. I'm also a bit lost." Her stomach rumbled. "And hungry, he he..." She smiled at the rabbit.

"Well you can come back to my house!" the rabbit girl said happily. She extended a hand. "Come on. My name's Cream, by the way."

Rainbow Dash took the offered hand. "Rainbow Dash," she said happily. Then she saw the winged blue thing floating over Cream's shoulder. "GAH! Parasprite! Quick, get a trombone!"

"Parasprite?" Cream followed Rainbow Dash's gaze. "Oh, that's my friend Cheese. He's a chao."

Rainbow Dash glanced back and forth between them. "Cream and Cheese, huh? Makes sense." And to her it did. Given some of the names of her friends and family, this seemed perfectly natural. "So...how far from your house are we?"

"Not far," Cream said. "It's just around the corner this way." The house was actually quite close, and Cream led her inside. "Mom! I'm home, and I brought a new friend!"

"That's wonderful, dear," a motherly voice said from inside. A rabbit woman in a matronly dress came into the room. Seeing Rainbow Dash, she gasped. "Oh, dear, what happened to your clothes?"

Rainbow Dash could only shrug. "I...don't normally wear clothes."

"Oh, but my dear..." the woman pointed to Rainbow Dash's front. "You really should. If nothing else, those could use the support, and it just wouldn't look right to only where a top."

Looking down, it was obvious the woman was refferring to the bulges that had so confused Rainbow Dash. "I'm...kinda new to...all of this," she replied blandly, inwardly wincing.

"Oh, dear, didn't your mother explain all of this to you?" At Rainbow Dash's helpless head shake, she led her into another room. "Here, let me explain it all to you. I'm Vanilla, by the way, Cream's Mom."


A half hour later, Rainbow Dash was sitting in the living room, dressed and blushing. She had gotten a rather blunt explanation of the function and purpose of each part of her recently acquired anatomy...and decided clothes would probably be a good idea. Vanilla had found some of her old clothes that fit her well: a rainbow striped spaghetti-strap top and blue jean shorts. They felt a little constricting, and - given what she'd learned - showed a bit more fur than she felt comfortable with like this. "Are you sure this is all right?" she asked Vanilla.

"Oh, of course dear," Vanilla said happily. "You have a wonderful figure, you should be proud of it. I admit, I'd have killed for a figure like that at your age."

Rainbow Dash flushed. "Thanks."

Vanilla nodded. "Now, you mentioned you were lost. Where are you from?" She served everyone carrot cake and tea.

"Ponyville," Rainbow Dash replied, enjoying the cake and tea. It was really good.

"Never heard of it, I'm afraid," Vanilla said, shaking her head.

Rainbow Dash blinked. "Umm...little town near Canterlot?" At Vanilla's continued confusion, she continued, "Uhh...Equestria?"

Vanilla shook her head sadly. "I'm afraid I've never heard of any of those places."

Cream spoke up. "You can probably ask Sonic. He's been everywhere, and probably would know how to get you home."

Rainbow Dash grinned. "So how can I find this Sonic, anyway? He sounds fast."

Cream nodded. "He is. He's the fastest thing alive."

Rainbow Dash's grin grew even wider as a familiar competitive glint appeared in her eye. "I'd like to put that to the test," she said eagerly.

"In that case," Vanilla spoke up, sipping her tea, "just pick a direction and run as fast as you can. He'll find you. There's nothing Sonic loves more than a race."

"I'll do that," Rainbow Dash said with a grin. "Thanks for the tea and cake, Vanilla. See you later!" Heading out the door, she picked a direction and ran as fast as she could.

For a time, she just ran as fast as she could, reveling in the speed. While her new body was unfamiliar to her, she was happy to discover she was just as fast as always. In fact, her ground speed seemed to have increased a bit, especially when she folded her wings against her back. Seeing a gorge, she leapt across, only spreading her wings at the apex of her jump to mantain altitude all the way across. Reaching the other side, she folded her wings and landed at a run, not losing any speed.

"Nice jump," a voice said nearby. "You're pretty good."

Turning to the voice, she saw a blue hedgehog running alongside her...backwards. His green eyes seemed friendly, and his grin was full of self confident swagger. His voice had been friendly but eager. He spoke again. "So just how fast can you go?"

Rainbow Dash smirked. "Why not test me?" she said happily, pouring on the speed. Before, she had just been running for fun. Now she was going all out. She quickly pulled away from the hedgehog.

Before long, however, he'd caught up. "Not bad," he shouted out to her. "But can you keep up?" He began to pull ahead.

Rainbow Dash pushed herself even harder, but he kept just ahead of her, always just a little faster. He was playing with her, showing off, not even hitting his top speed. She found herself grinning. Finally, she'd found a real challenge for her speed. Leaping into the air, she spread her wings and flew, pouring in all her strength. As the arc of light appeared before her, she shouted, "Let's see you keep up with the Sonic Rainboom!" She poured on the speed as the arc sharpened to a point.

To her shock, however, an identical arc of light had appeared before the hedgehog, sharpening to a point. At the exact same instant, both arcs broke, releasing a deafening explosion of sound as the two streaked forward faster than the eye could see, a blue contrail alongside a rainbow across the ground.

A brief glance back showed Rainbow Dash something that shocked her so bad she nearly lost her flight. The rainbow wave released by the Sonic Rainboom had been disrupted by a blue wave released when the hedgehog had broken through, and the two waves had interacted creating a rainbow curtain that undulated in the air like light refracting off water. It was so beautiful it took her breath away.

A few minutes later, Rainbow Dash began to run out of breath, and was forced to land and slow down. Her opponent also slowed down with her, although he didn't seem anywhere near as tired. "You're REALLY good!" he said happily, grinning from ear to ear. "I've never had anyone keep up with me for that long even in a normal run...and you're the first I've raced in a long time to break supersonic speeds. I'm Sonic the Hedgehog. What's your name, cutie?"

Rainbow Dash found herself blushing. "R-rainbow Dash," she said, still trying to catch her breath.

Sonic grinned. "Well, how about we go refuel? That kinda run really takes it out of you. After, I'll help you with some training to build up your wind, so you can keep up those speeds for even longer. Can't wait to see what you can do then!" He gestured towards a town that was now visible. "Come on, Dash! My treat!" He dashed off towards town at what for him was a gentle jog.

"Wait up, Sonic!" Dash ran after him. She couldn't wait to see what happened next.