Mender set the chair down on the porch, then shook himself to free any dust that had gathered on him from carrying the rocking chair. Dear Celestia, the chair was caked with dust. He stifled a sneeze as he went back inside to fetch his duster.
As soon as he found it, he went back out, held his breath, and began sweeping off the dust. A small blanket of dust settled around the chair when Mender finished, but didn't stay long as a light breeze picked it up before it could settle. Being on a hill like this did have that small benefit...though the thought of a tornado hitting this shack had Mender shudder a bit.
He couldn't help but admire his completed work. The chair looked old still, but had a feeling about it that said it was like new, though he couldn't pinpoint why.
He figured he earned the opportunity to sit on that chair...but then his thoughts wandered back to that basement...and that door. Augh, that door still bothered Mender immensely. It was a curiosity that mocked him in his own home, and it made him angry. He hated not knowing things that seemed so close within his reach, but just beyond his understanding.
He stood there for a moment, pondering his options. He could always chuck the door in the nearest trash bin and forget the whole ordeal, but it was just too strange to toss out so easily. A second option was to ask around town about it...which seemed less than helpful considering this door was sitting in a basement in an old shack for Celestia knows how long.
That left the third option, which was researching it. A good point to start from, to be sure, but Mender had no idea where to begin...but he at least knew of a place where he could get some answers.
The Ponyville Library.
As he trotted back into Ponyville, he discovered the library was pretty hard to miss, what with it being the largest tree he had ever seen. He wondered how he missed it before when he left the hospital, but a small headache came back when Mender remembered a pink frazzled mane and a scent thick with the smell of sugar. Pinkie was quite the distracting force, he reasoned to himself.
The large tree had two rounded windows, one on the first floor and one on what was presumably a second floor. The second floor idea was more prevalent as he spotted a balcony on the left side of the tree near the window. A planter stood on both sides of the door with various bushes coming out of them. It seemed like a quaint, quiet place, but a nagging thought at the back of his mind told him this place had seen more action within its walls than any other place in Ponyville.
He knocked on the door, and heard something crashing inside. He swore he heard grumbling and some shuffling steps as a small purple dragon with green eyes and spikes opened the door.
"What do you want, dude?" The baby dragon asked.
"Is this the Ponyville Library?"
"Yes, it is. Why, are you new here?"
"I guess you could say that...even though I've been here for a little over two weeks. I haven't exactly adjusted to this town yet, on account of a personal injury I had to recover from in a hospital for most of that time."
"Whoa, you serious? What happened?"
"Let's just say I was roughed up in my own home by three attackers, who have since been caught and they have apologized to me for their rude behavior." Mender wanted to be vague about this, as he didn't feel comfortable admitting to anyone but himself and those in the hospital that three fillies had caused the damage to him.
"Ah, well, I'm glad to see you're still standing. The name's Spike, and welcome to the Ponyville Library!" The dragon extended a claw to greet him.
Finally, he thought. Someone who made that gesture to him first. He reciprocated by extending his own hoof.
"Able Mender, glad to meet you, Spike."
"Great! Now that that's out of the way, what brings you here?" The dragon walked inside, and Mender followed and took in the sight before him.
Books, books, and more books. Books on shelves, books in stacks, books on the table carved out in the center of the room. If this didn't scream to him that this was a library, he didn't know what was. To the left of the entrance was a door that led to what he presumably thought was a storeroom for more books...until the scent of food from beyond it told him it was a kitchen. A set of stairs rounded the interior of the tree near that door, leading up to a small bed. He didn't peg a library like this to also be a home, but it made this place all the more comforting to him in how seamless the two seemed to mesh within this tree.
The sight of the place almost completely had him forget why he came here...almost.
"Oh, well, I've kinda got a door problem."
"...dude, the town locksmith lives near Sugar Cube Corner," Spike said, an annoyed look on his face.
"Not that kind of problem," Mender growled, "I mean, this door is locked, but it isn't even attached to anything anyway!"
"The carpenter lives next to the locksmith." Spike was getting more annoyed, and Mender sighed.
"...again, not that kind of problem. It's a magical door." Mender thought for a moment before continuing, "You know, I didn't expect the the town librarian to be so snippy about this. I came here for help, you know."
"What? Oh no no, I'm not the librarian. I'm her personal number one assistant!"
"Number one personal assistant?"
Before Spike could respond, the kitchen door swung open. Mender's eyes glassed over as he turned and saw a purple alicorn enter the room. Her mane and tail were straight, a deep dark blue color with pink and dark purple highlights on both. Her eyes kept with the theme with those being a different shade of purple, and her cutie mark was a six-pointed pink star with smaller stars surrounding it.
"Hello Spike. Who's your friend?" she asked.
"We're not really friends yet, but this is Able Mender," Spike replied. He left the room to go to the kitchen, probably for a lunch break, Mender thought.
"Well then, hello, Able. I'm Princess Twilight Sparkle, but please, call me Twilight. I'm still not used to this whole Princess thing." Mender caught a slight blush in her cheeks. He didn't think she could sound any more modest at that point.
"A pleasure it is then, Twilight. Please, call me Mender though. I haven't been called by my first name in a long time, and I'd rather not have that change now." Mender rubbed his neck and sheepishly smiled.
"Alright then, Mender. So, what brings you to the library?" she asked.
"Well, it's a door problem."
"Oh, but the locksmith lives near Sugar Cube Corner," Twilight remarked, her head tilted slightly.
Dammit, not this again. "No no, it's a magic door. One that's attached to a door frame, but not to anything else."
"Magic? Really?!" Her eyes lit up with excitement, which caught Mender off guard a bit.
"Uh...yes, it's a magic locked door. It's got a keyhole, but I don't know where the key is."
"Hmm...well, if it's a magic door, maybe it needs a magical key?" Her reasoning was sound, if somewhat obvious.
"Yep, sounds like a decent conclusion, but I was wondering if there was any other way to open it. Blasting it with a surge of magic, maybe? Maybe even breaking the door down?"
"I'm not so sure those ideas will work," Twilight responded.
"Oh? Why not?"
Her horn glowed magenta as she lifted a book titled "Magical Crafts and Curiosities" off one of the shelves and started sifting through the pages. She stopped at a page in the book and floated it in front of his face, which detailed the use of magical doors.
She began her explanation. "Magical doors are an enchanting spell many ponies have yet to fully understand. What they do is they create a space somewhere in the world, and this door essentially acts as a gateway to that area. I've actually dealt with a similar doorway like this before. The door I used was built into the wall, but had no keyhole. I had to use magic to open that door, which let me out on the other side past the wall."
"However, yours isn't built into anything, and has a door with a lock on it. Ideally, doors like this were used to carry personal rooms for their owners to use at will, but it's very sensitive magic. If the door is forced open using a magic spell, it will sever the link between the door and the space that is created. Physical force can be used to break down the door, but that's difficult as the doors themselves are usually magically reinforced to prevent that from happening."
"Instead, these doors can only be opened with the use of an enchanted key specifically attuned to the door. More than one key is usually made by the owner, since without a key, the door cannot be opened. Even if they knew the counter-spell to dispel the barrier they placed on the door, that doesn't work because it's so attuned with the room's location that it also severs the link if it's attempted."
Her voice turned cold as she spoke these words. "It also goes to reason that if the connection is severed when a pony is in there...they are trapped forever in that space. This is why this enchanting spell is used so little here in Equestria. If improperly used, it can act as a permanent prison for the pony...or ponies inside of it, completely isolated from the rest of the world."
Mender tried to digest all this information carefully before he posed a question.
"Is it possible to reestablish this link at all when it is severed?" Mender asked.
"Well, if the owner is outside the space within the door, then yes. They can sever the link and reestablish it at will...but if they're inside the space, then no. Inside that space are all objects created with that pony's mind...but he didn't create a real door for that space, only a 'fake' door that's bound to the 'real' door. If the link is broken, the 'fake' door vanishes, trapping the pony inside completely."
"Wait. How do they know that, anyway? That doesn't sound like information that comes from just theory alone."
She pulled out a second book from the shelves titled "Important Magical Discoveries Across Equestria, Thirteenth Edition." Twilight flipped through the pages again, and stopped at a point talking about the magical doors and set the book on the table as she continued her explanation.
"An experiment was conducted using these enchanted magic doors by two ponies, Old Mindley and Sagely Thinker. Mindley made the doorway and enchanted it, and Thinker entered the space created by Mindly. Mindly took the key from inside the space and locked the door, then severed and recreated the link to that room. When he reopened the door, Thinker was still in there, safe and sound."
Mender showed great concern about the experiment. "Wait, how was Mindly so sure of this? What if when he severed the link, he destroyed the space with his friend in it? And when he reestablished the link, what if he remade his friend in there and none were the wiser?"
Twilight shook her head. "When Mindly and Thinker proposed this experiment to Princess Celestia, she had those same concerns. However, the two proposed a solution to the problem. Celestia would take Thinker aside, and he gave her certain questions and their correct answers. She was then to ask him those same questions that only he knew the answer to, but Mindly did not. Therefore, if he came back and gave the wrong answers, or didn't have any, she would know that Mindly had lied."
Mender was baffled. "Damn, that's a genius solution...if still a bit crazy. I mean, Thinker was putting so much trust in Mindly. His life was in Mindly's hooves at that point!"
"True, but Thinker had faith that his friend wouldn't take his life. If he didn't, they never would have proposed the experiment to Celestia in the first place."
"I...suppose that's true. So...what happened next? They did the experiment, she asked the questions, and Thinker got them right?"
"That's the basic gist of it, yes. For the most part, the experiment succeeded." Twilight's voice trailed off at the end.
...wait a second. "For the most part?"
"While he was indeed the real Thinker, Mindly added extra questions to confirm his friendship with him...and to everypony's surprise, Thinker had no knowledge whatsoever about Mindly at all...he completely forgot they were even friends."
The shock was plain as day on Mender's face. "How did that happen? That's impossible!"
"Nothing's impossible, Mender. It's just that nopony has been able to explain that loss of friendship between them. It's been theorized that taking the created key out of the room was a possible factor that was responsible for that loss of memory, or even that time functions differently within that space, but nopony knows for sure...not that they can find out anymore. Celestia forbade any other experiments on the matter. She realized at that point how dangerous these enchanted doors are, and banned their use throughout Equestria. This was not only due to the potential dangers of trapping ponies in them for eternity, but also for erasing all the memories of those inside of the one who created the room. Those two negatives alone far outweighed any benefits she could see from using these rooms for any good to come from them."
She finished her explanation at last, and Mender was deep in thought, processing all this data into his head.
He spoke after a minute of thought. "So Twilight, you're telling me that I am in possession of an illegal enchanted door that I can't open because I don't have the key...and if I somehow did find the key, it's illegal for me to use it to open the door?"
"More or less."
"Alright...okay...small question." He cleared his throat, then snapped. "WHY DIDN'T YOU TELL ME THAT FIRST?!"
She was taken back by Mender's sudden outburst. "I-I-I-"
"Twilight, you may as well have told me that I'm bucking sheltering POW's from the Lunar Rebellion!" he snarled.
She suddenly straightened up firmly. "MENDER!"
Twilight's yell was much louder than his, and it snapped him out of his momentary rage. His figure wilted as he saw smoke begin to trail from her mane and tail...which faded as she spoke calmly.
"Mender...I'm sorry. I wanted to save that bad news for last. I thought it was important that you understood how dangerous these doors were. Tell me, what you would have done with that door if I simply told you that it was illegal?"
"I...would have tossed it out or burned it immediately."
"Precisely. Now you should know that there may in fact be a pony just past that door. If you tossed it out, the pony might come out and be confused as to what it's doing there...and if it was burned, you would have doomed the owner to a fate worse than death."
Mender couldn't say anything. Despite all he learned from Twilight about this door, he could still hardly believe that he may have come -this- close to trapping a pony for eternity. He remembered that yelping noise that sounded so strange to him back then, and realized she could be right. His insides twisted and coiled at the thought.
"Well then, what...what should I do?"
Twilight's mood went from sad to hopeful at the question. "Well, like I said, you'll need the key to open the door, of course. But if there's a pony in there, you can still talk to them."
"I can? How?"
"It's a side effect of the link tethering the space to the door. It carries sound waves quite easily as if the door were hollow. That will be the only way to communicate with anypony inside, assuming they are even in there," Twilight finished.
"Well then, I guess it can't hurt talking to a magic door then, for better or worse. Sounds crazy to me, but I've seen and done crazier," Mender chuckled. "Thanks for the help, miss Twilight."
"Anytime, Mender!" She called out after him as he left her in the library.
She was quite the smart cookie, and was very rational. Heck, she even managed to calm him down while he was sputtering mad! The only other pony to do that was his superior back in the army...but that was under different circumstances.
...and then he remembered how she introduced herself. She said it so calmly he didn't catch it at first, but as he left, his stomach did a barrel roll.
He got mad at, and possibly ticked off, a Princess.