It had been a little while since Books saved Swiftwind.
Aaah, Swiftwind. Every time he thought back to the hospital...
Books was...well, to put it bluntly...
Books was peeved.
And to think, this time, it's my own fault.
Only once he'd recounted the experience of saving Swiftwind to Ferrix did he realize the enormity of his error.
He was now bound to her. Totally and completely.
Oh, sure, the Vow could technically be broken.
At the cost of their lives.
Neither one were willing to risk it.
Books decided that today would be the day he'd get some answers about his own internals.
So, naturally, he decided that a few other test subjects were needed.
"So, we are seeing Twilight Sparkle, because she, among all the ponies here, has the equipment needed to do a comprehensive scan of our internals?"
Books nodded absently at Silver Tongue's question. "Yeah, don't let the bi-monthly near-breakdowns I've told you about fool you. When Twi's is presented with a simple problem, she usually finds three simple answers, and works on a complex one so that the problem stops fer good."
Adam, in his simple Earth Pony guise of Golden Stalk, chuckled as well. "Though, let's be fair. She hasn't been present for one. The retelling can't hold all the terror of the actual event."
Books mock-cringed. "Oy, we don't talk about the event!"
The two males laughed as Silver Tongue looked between them. "Is this what you call an inside joke?"
Books stopped and nodded again. "In a sense. I think Ponyville's cursed. Something exciting tends to happen more often than not, at least, e'er since the Elements found their Bearers. Stick around and you'll pick up a few stories."
Silver looked around carefully as though expecting danger to pop out of any alleyway, and Books decided to sneak a compliment in. "On another note, you've made great progress with modern forms of speaking. Just gotta get you used to nicknames, slang, verbal tics, shortening of words, contractions...but hey, you've made great progress on the vocabulary front!"
Silver leveled a glare at Books. "I am not slow. Just unused to this new society."
Books waved a hoof at Silver. "Never claimed you were. Anyways, we're here."
Books knocked on the door to the library, and Spike opened it. "Oh, hey A-"
Books shoved a hoof over Spike's mouth and shook his head slowly. Spike's eyes widened, and he nodded. Books lowered the hoof, and Spike rubbed the back of his head. "Heh, sorry Books. Forgot. Anyway. These two your friends?"
Books looked back at the two behind him, then returned to looking at the dragon. "After a fashion. Twi in? We've got questions we think she could answer."
Spike shook his head. "She's with the others, Rainbow Dash said something about the Wonderbolts Academy, and everypony else went to her place."
Books nodded. "She's comin' back, though, right?"
Spike nodded. "Yeah. You could wait around if you want."
Books, Silver, and Golden walked in and sat at one of the tables. "Spike, think you could find me a more advanced Mind Magic tome? I was thinking of putting up more mental defenses."
Spike went to a shelf and pulled out a rather hefty-looking book. "Mind over Grey Matter. Not a bad title."
Settling in for a wait, Books began to read in relative silence.
-----
"Sire, in all sincerity, please go buck yourself."
Abel merely chuckled at Adam's remark.
Twilight had finally returned home to see the three changelings in disguise sitting in the library.
When she was informed they were here for medical testing, the grin on her face could nearly compare with the sun for how well it lit up the room.
This had led directly to the basement, where all three had shed their disguises.
Abel had suggested they start with the more common type of changeling first.
Which had led to Adam being strapped into a chair that eerily reminded him of Dr. Frankenstein.
Or would it be Flankenstein here?
A small army of sensors were attached to Adam's body. One to a foreleg, at least half-a-dozen EEG's on his head, an EKG on his chest, and...
Well, Abel was lost, but he had every confidence in Twi's medical capability.
Of course, he had drawn the line at her trying to get a blood sample on her own.
That was highly painful if you didn't do it right. Namely, at a joint, where there was a natural thinness to the chitin.
Even then, Adam had winced. Abel wasn't surprised to see that the blood in the syringe was green.
Of course, Twi was all for causing Adam pain, seeing as how Adam had forgotten to soften his chitin so that she could get readings for a few minutes.
Though Abel did have to admit, seeing her bank of machines spitting out error after error and seeing her hair become slowly more manic did have an unusually entertaining quality to it. Right up until Adam was reminded of the 'event'.
Afterwards, as the machines began taking in all the data they could obtain, Twi cast a spell from one of her advanced medical spellbooks. It reminded Abel of an MRI.
"Fascinating. It would appear that changelings share many characteristics with ponies, while being unique in so many other ways."
Abel grinned. "Strike that, reverse it. We were here first, after all."
Twilight turned to Abel, glared, opened her mouth, raised a hoof, paused, closed her mouth, and rubbed her chin with her hoof. "I'd forgotten about that history lesson until now. I'm just so used to-"
Abel cut her off. "We can discuss relative histories later. Medical results, please."
Twilight grinned. "Did you know you have exo- AND endo-skeletons?"
Abel raised a hoof and looked at it. "No, I had no idea."
Twilight forced out a laugh and continued. "It would also seem that you have a very...unique digestive tract. One that allows for organic food to be consumed, as well as love."
Abel turned to a specimen collection jar and hocked a chunk of gelatin into it. "Really? Fascinating."
Twilight groaned and rolled her eyes. "Are you going to undercut all my discoveries by demonstrating that you already knew?"
Abel grinned. "Nah, that's about all I knew, really. I'm just messin' with ya, Twi. I'd do it less, but you make it so easy!"
Abel swore he saw Twilight's right eye twitch. Fortunately, the bank of machines chose that moment to ding and start printing out results.
This caused the mare to zip over to the paper in question and begin reading it in earnest. Several times she muttered 'fascinating' or 'I see' while nodding to herself. Eventually, she turned back to the changelings and saw them all staring at her.
"Care to share, Twi?"
Twilight blushed for a moment and began to read off the results.
"Well, for one, the heart rate of a changeling at rest appears to be about 80 beats a minute. There's also an interesting section of the brain that tends to be sporadically active, causing various spikes of various waves of activity, most notably Delta and Theta waves."
"Gonna blame the Hive Mind on that one."
Twilight put a hoof to her chin. "It makes the most sense. If I test myself, we might get similar readings... One of the more obvious differences is that changelings do not generate their own source of internal magic."
Abel looked intrigued. "We kinda figured that one, what with needing to feed off of those that do. But...you mean we're entirely cut off?"
Twilight turned to a bookshelf and used her magic to pull out and unfold a diagram of a pony body. Pointing to a set of glands, the unicorn entered lecturer mode. "Ponies have these glands, aetherial converters, which provide us with our internal stores of magic. They also take in the ambient magic of the land and convert it into energy we can use. Changelings...seem to lack this. And all life needs magic to live, so..."
Abel nodded. "So we took to feeding off of those that have magic to survive."
Twilight put the chart back and nodded. "Now, if you'd known, and managed to give yourself a set of those glands..."
Abel grinned. "Oooooh. Possibilities. Adam, store that info. Next ruler we have, needs to do this."
And they all felt the ecstatic glee that filled the Hive Mind at this particular revelation.
Continuing on, Twilight looked at the list of results. "Blood pressure is about 110/68. Lungs and respiratory rate appear nominal. What is utterly fascinating is the chitin and its capabilities. When in 'armor' state, no readings can be observed, and I suspect puncturing it is very hard. When 'relaxed,' readings can be taken, and is in fact quite soft."
"And yet," Abel quipped, "We can't feed off him. So whatever is keeping his energy on lockdown, it ain't the chitin."
Twi rubbed her hooves together. "We should figure that out one day...Internal temperature is...oh my. 80?"
Abel let loose a low chuckle. "We don't have quite as good a temperature regulation system, Twi. Hibernation an' all. We tend to avoid extremes if we can. 'lest, we did, before we had a warming spell."
Twilight nodded and pulled out the vial of blood from...wherever she'd stored it, and inserted it into another machine. It began to whir, getting steadily louder, until finally it cut out and wound down far quicker than it wound up. Then there was a few noises, of extremely delicate machinery moving, and another sheet of paper began printing out from near where the blood had been inserted. Twilight took a look at it and started muttering. "No...no no no...that's just...not possible..."
Twilight cast a glance at Abel before uttering a single question. "Have any changelings ever successfully bred with ponies?"
And that was the moment in which the Hive Mind stopped for one second, in total, absolute shock.
Abel carefully compiled his information before replying to the mare.
"As far as I know, our...history has prevented us from doing as such. With recent developments, I.E. this Hive Mind...I can tell you right now none of mine ever tried, believing the offspring of a pony-changeling union, if we even could, would be a dead giveaway. Why do you ask?"
With a level voice, Twilight responded. "Because, you have an eerily similar number of genes to ponies. It's highly likely that you could. You're just missing one set."
Every changeling blinked rapidly for a few moments before Abel put a hoof to his head. "Ow. Ow. Ow. STOPPIT."
Abel then glared at Twilight. "Gee, thanks Twi. Now you've inspired those that want foals to go have slash make them with their partners and reveal themselves. I'm going to have a migraine for weeks, and the fallout will be massive."
Before Twilight could speak up regarding this development, Adam decided to make his discomfort known. "Can I get up now? All these devices are staaaarting to irk me."
Twilight turned to him and nodded, and in a flash of green, all the attached monitoring devices separated themselves from the changeling. Adam got up and stretched, then assumed his normal Earth Pony guise and nodded to Abel. "Right, I'll be off, then. Take care, sire."
As Golden Stalk made his way up, Swiftwind made her way to the chair. "This will not hurt?"
Abel sighed. "Taking the blood for analysis will hurt, a little. Everything else shouldn't. As long as you remember to soften your chitin for her, that is."
Before Swiftwind could complain, Abel had already pricked her and taken a sample of her blood. This did of course earn him a glare, but Abel passed the sample over to Twilight anyways. She nodded and put it in the machine before enveloping the myriad sensors in her purple aura and attaching them to the white changeling sitting in the examination chair. Just as the last sensor was placed, the centrifuge started to die down. The two sets of data began printing at nearly the same moment, and Abel took both of them in his magic while Twilight scanned Swiftwing in hers.
"Fascinating...the main difference between the two is the lack of the painkiller gland. Every other minor difference can be attributed to a differing of gender...for the moment."
Abel wafted Twi's results in front of her, and the eager mare pounced, reading them all and nodding slowly. "Yes...that makes sense. Most of these results are similar, if not outright alike. But the DNA analysis is most interesting. It appears to have the same number of genes as the last. What we could really use, though, is-"
Abel held up a hoof. "We are NOT knocking up the only albino female, nor am I getting any of my Hive pregnant, just for your experiments, Twilight. And that goes double for pony-kind and changelings interacting for the time being!"
Twilight had the decency to blush as Abel continued. "IF, and this is a big IF, IF I or Swiftwind here choose to propagate the line of white changelings, it will be because we've found someone we love deeply. Not for science, not for one-night stands, not out of a sense of obligation. We'd do it because we want to, not because we have to."
There was a beat. And then, from the examination chair, Swiftwind spoke up.
"You would make an excellent sire to my young, my lord. Shall we get started now?"
-----
In one of Canterlot's towers, sitting in her room, Celestia was enjoying a day away from court.
What? She scheduled them every so often.
She was just about to bite into a delicious-looking masterpiece of a cake, the creator had named it 'Death by Chocolate.'
Frankly, Celestia doubted that.
The fork with the cake on it hovered closer.
Closer!
And then a sonic disturbance rocked the tower.
One that went to a very specific tune, knocked Celestia's concentration off, and caused the cake and fork to fall to the floor.
If one listened, one could just about make out the tune coming from Ponyville. One that sounded remarkably similar to a certain changeling king.
"WHAT THE BUCK DID YOU JUST SAY?!"