Sheldon opened the door to the empty, unused room in the basement of the university, eyeing the number 43 chalked up on the chalkboard. Once again, he allowed himself a Sheldon-esque chuckle at his biggest Bazinga to date. He reached into his backpack and withdrew a small metallic box, setting it down and flipping it open to reveal the wormhole generator inside. The wormhole generator had been real, and he had fooled Wolowitz and Koothropali into thinking it was a prank. Prank-ception, to be sure. Of course, the 43 was his personal hacky sack record, it had nothing to do with the wormhole generator. Why would they think for a second a mind of his caliber would forget how many parallel universes he had checked?
Nevertheless, he calibrated the machine and set it one up from what he had set it to last week, pulling out his personal voice recorder. "This is Dr. Sheldon Cooper; wormhole generator test number...47," that was what the number was up to by now, "In my never-ending quest to find the universe which will allow me to obtain superpowers, I have checked 46 empty parallel universes, but I shan't give up if it means potentially ignoring superhuman abilities." he flicked the switch and a wormhole spun into life. It was a different color every time, though mostly cooler colors; black, blue, and purple. This one was a bright pink color. Puzzled, Sheldon stepped nearer to the wormhole, inspecting it at every angle. It seemed safe; calmer than most portals, though he couldn't see through to the other side. Slowly, and cautiously, he peeked his head into the wormhole. It felt like sticking your head into a jet of water that pulled you forward, though without getting wet.
A glimpse of the universe caught his eye, and he saw brightly colored plants and trees, a brilliantly blue sky, and fields of light green grass. Horrifying.
He shuddered at the thought of an entire parallel planet of nature, and pulled his head out against the wormhole, making a mental note of the settings he had used to discover this universe.
Suddenly, he felt a large push from behind, sending him headfirst through the wormhole. For a moment, he was suspended in the pull of the trans-dimensional link, but was then deposited heavily onto the brightly colored dirt path. He scrambled to stand, uncoordinated and discombobulated, until turning around and seeing the wormhole snap shut.
"Oh dear..." he said.
He turned to face his surroundings, preparing himself for the task of building a new wormhole generator with nothing but nature. He felt...off. Unbalanced. He looked down at his body and made a shocking discovery.
He wasn't wearing any pants.
But not only that, his beloved bipedal frame had been taken from him and replaced with the Technicolor body of something that looked almost equine in nature. And it was; he had four legs, each one capped with a pair of cloven hooves, covered in a thin layer of fur so that he was the same color throughout his body. Thankfully, he still had his shirt, and paused for a moment to wonder why the wormhole had taken his pants but not his shirt. Dismissing it as pure natural coincidence, he attempted to navigate with four contact points instead of two, and found it actually quite difficult. He shambled forward a few steps, awkwardly attempting to navigate the dirt path in front of him whilst thinking logically about his potential courses of action.
If there was a dirt path, then there was obviously intelligent life. Or at least, some form of mobile life. So this wasn't just a planet of plants, which was somewhat relieving. The g-forces of the planet seemed similar to Earth; it wasn't extraneously difficult to move, though having four legs instead of two was quite encumbering.
He looked out around his landscape, searching for some form of intelligent life. He thought he spotted the silhouette of a house on the horizon; perhaps there were humans here, or at least something that could help him. He wondered what form of technology they had, wondering how difficult it would be to construct a wormhole generator by hand-er, hoof, in his case.
One long, difficult trip later, Sheldon had somewhat gotten the hang of quadrupedal movement, and had finally reached the house on the horizon. It was certainly a house, design similar to a Victorian-Gothic era house with a thatch roof. He made his way around it, discovering several other similar houses dotting the landscape, haphazardly arranged in some primitive village layout. But that wasn't really the most obvious thing.
Ponies, ponies everywhere, of every size, shape, and color. They all had astoundingly large heads and eyes; he wondered if he was similar in biological structure. They were making their way around what he assumed was the town commons, holding discussions and doing business from market stalls.
Suddenly, a pink colored pony appeared right next to him, "Hello! You're new in town! I know, because I know everypony! My name's Pinkie Pie, what's yours?"
Sheldon was caught off guard at the ponies' abruptness. "Interesting," he observed, "You seem to speak English, well that's convenient."
The pony, Pinkie Pie, looked confused, "What's English? I'm speaking Equestrian, and so are you!"
This pony obviously had no idea he was actually a human and not a pony, so Sheldon decided to play along, if it was necessary for survival (but only if it was necessary for survival) "Ah, yes, of course," he said, forcing a smile, "How foolish of me."
Pinkie Pie giggled. How atrocious, he dearly hoped she wasn't like this all hours of the day. Speaking of which, how long was a day on this planet? He had so much to learn, but his first concern was securing a way back home. "So, uh, Pinkie Pie," he said, "You wouldn't happen to know where I can find a wormhole generator on this planet, do you?"
Pinkie Pie was confused again, "A what?" she said, smiling all the while.
"I assumed as much," Sheldon conceded, "Tell me, what is the most advanced form of technology your kind has?"
Pinkie Pie thought for a moment. She certainly was trying to help; it wasn't her fault that she wasn't a genius like him. "Well, um, I think that would be the cloud factory in Cloudsdale!"
Sheldon had no idea what a cloud factory was, nor did he know anything of this 'Cloudsdale', but if they had technology, that's where he needed to be, "Alright, can you take me to this, 'Cloudsdale'?" he requested.
Pinkie Pie giggled at his request, "You can't go to Cloudsdale, silly!"
Sheldon was puzzled, "Why not?"
"Because," Pinkie Pie explained, "You're not a Pegasus!"
"Pegasus?" Sheldon repeated. He shook his head and smiled, "No, those aren't real, they're just myths!"
Pinkie Pie rose an eyebrow along with a confused smile, "Uh, then what do you call that?" and gestured to a nearby pony.
Sheldon turned to discover the pony standing next to him had a pair of wings attached to her back, right below the shoulder blades, "Astounding," Sheldon said, admiring them, "I suppose we were on to something with that old myth."
"Who's we?" Pinkie asked.
Sheldon turned back to her, "Oh, nothing," He assured, thinking fast, "Okay, um, how about this; Pinkie, can you take me to the smartest pony you know?"
"That would be Twilight Sparkle!" Pinkie explained, "She's the smartest pony in Ponyville, maybe even in all of Equestria! And she's my best friend!"
"That's great," Sheldon said, "Can you take me to her?"
"Sure!" Pinkie assured, bouncing away, "This way, follow me!"
"Now hold on!" Sheldon requested, shambling across the ground, "I haven't gotten quite used to having four legs!"
Pinkie Pie slowed down and waited for him, "You know, you're kinda weird, but I like you; I'll be your new friend!"
Sheldon wasn't about to explain his aversion to social interaction to this trans-dimensional pony, and simply nodded, "That's great, now which way is this 'Twilight'?"