//------------------------------//
// Underworld Tour 
// Story: Twilight's Kingdom of Steam 
// by Darthvalgaav 
//------------------------------//

“You stupid little,” hissed Overkill under her breath. Twilight’s ear’s flattened as she glanced around her, wondering if the guardsmare’s voice had traveled far down the hallway of steel and copper tubes. Thankfully, there weren’t very many ponies nearby who weren’t in her party. The only ones she saw were Dr. Sparks and Blood Moon, who were both providing a tour of the facility. Moreover, while thestrals had very good hearing, the hallway was full of noise. From the clopping of their hooves on the metal floor to loud clanks that echoed through the halls, the words were mostly drowned out. Unless, of course, they were focusing on them and waiting for Twilight to ask them a question. Thankfully, neither of their ears twitched at the sound of Overkill’s voice and their heads were still looking straight ahead. Nothing showed that they had heard anything.
 

Still, Twilight didn’t want to take any more chances. Her horn began to glow as she cast a swift spell around them, one that she had picked up from her time at Celestia’s School for Gifted Unicorns. The spell was fairly simple, it altered the vibrations created when a pony was talking to either drown them out or make it like they sounded like something else. For this, Twilight chose silence since the words would come out as random gibberish. Normally, Twilight didn’t like to use this spell since it wasn't in any of the books. Rather it was one that had been passed around by the students so that they could gossip in class without anypony hearing what was really said. The only problem was that others could still see their lips moving and a skilled enough lip reader would be able to figure out what they were really talking about. Not to mention the horn glowing was a dead giveaway. For her part, Twilight had glanced at the spell a number of times, seeing it as nothing more than a waste of time and magic. Now, however, it couldn’t hurt to take a few additional precautions.
 

“How could you not tell us that you had a brother here?” Overkill continued, Twilight noticing that a vein had appeared on the mare’s forehead. At the same time, the purple princess also noticed that Overkill seemed to be fighting to keep herself from reaching for her blunderbuss. And it looked like it was a losing battle as her hoof inched ever closer! “Do you understand how helpful it would have been to have a pony on the inside? One that we could contact or spy for us? A backup in case we needed an emergency escape? We could have contacted him before we left Automahollow and asked him to look into some of the top secret projects around him. Or found out if there were any rumors flying around. Did you not think that would be helpful? Well?!?”
 

“Ah, I did say that Mad hates me,” said Wild in a calm voice as if he were discussing the weather, a small smile on his face. “If I did try to contact him, he’d more than likely warn, warn, warn everypony about us. So I really didn’t see any point in telling any of you.”
 

“Not any…” mumbled Overkill as her face turned red while her eye twitched. “Are some of your brain cylinders misfiring in there? Because I’ll gladly deck you if it means it’ll fix them.”
 

“Actually, Tinkers have found that simply hitting a machine won’t help fix the prob-” Wild was suddenly cut off as one of Overkill’s wings was pressed against his throat. While not dangerous, there was an implied message there that Wild got loud and clear.
 

“If it’s that bad you should have warned us!” growled Overkill as her eye continued to twitch. “Any information would have helped us in formulating a plan. We are in hostile territory and knowing who to watch out for would have been good to know! Plus, we were just now caught off guard. That tends to kill thestrals in my line of work! Do you even understand the importance of this mission?!?”
 

“Oh, yes, yes, yes,” began Wild as Overkill pulled her wing back. “But I really don’t think that applies here. This isn’t a war zone caused by rebels. The only way we’d get killed around here is if you touched something you shouldn’t or shot something randomly.” As Overkill seethed with anger, Wild tilted his head in a very innocent way. As if he had just thought of something. “Come to think of it, that might very well happen with you around. I guess I should have warned you about that sooner.”
 

What happened next occurred in a flash. Overkill’s face was burning brighter than ever while steam was shooting out of her ears. With teeth gritted so tightly that they might soon shatter, the mare pulled out one of her blunderbusses before pointing it at the good doctor. She might have pulled the trigger had Twilight not seen this and levitated the weapon out of her angry hoof.
 

“Overkill, I understand you’re angry,” said Twilight as she spoke in her calmest voice. “But right now isn’t the time. We’re on a mission, remember?” Slowly, she brought the weapon back to her personal guard, who was still seething in rage. Once it was close enough Overkill swiped at it like a cat would with a toy mouse dangling from its tail. As she held the weapon, Overkill took several hard and labored breaths before putting it back in its holster. Still, the mare seethed in rage, shooting Wild the dirtiest of looks. With a soft sigh, Twilight’s horn lit up and, with a soft pop, teleported between the two in order to separate them.
 

Both ponies looked shocked and surprised by this, eyes widening while Twilight’s wings pushed them further apart. The flash created by the teleport also caught the attention of the two thestrals in front of them, turning their heads to look at what had caused it. What they saw was Twilight separating the two as an embarrassed smile appeared on her face, beads of sweat beginning to appear as she laughed nervously. She could see their eyes move from her to Overkill, who was still slightly foaming at the mouth, and then to Wild, who eyed Twilight’s wing with curiosity. It became very clear to her that they had read the situation, giving the princess looks akin to pity before looking ahead once more. Twilight’s face was slightly red now, fighting the urge to hide her face with her wings while also wishing lightning would just strike her dead. The only good thing was that she had managed to cut off the magic in her horn so that they didn’t know she was using magic. That would have made the whole thing worse.
 

Now that they had some measure of privacy back, Twilight pulled her wings back while her horn lit up once more to cast the noise muffling spell. “Overkill, I expect better from my personal guard.” she hissed. Her words caught Overkill off guard before she lowered her head a bit in shame. “Next time you want to chew someone out or have a problem with them, wait until we are alone. Is that clear?”
 

“Yes, ma’am,” muttered Overkill as she glanced over at Twilight briefly. Twilight’s eyes softened a bit as she saw the look of disappointment Overkill had for herself. But before she could say anything else, Overkill’s gaze averted to the floor while both her wings and ears drooped.
 

With a sigh she turned to look at Wild Theory who was looking at the two of them with…curiosity? It was a little hard to tell with his face so calm and almost featureless. “Dr. Theory, you know that Overkill has a point. You should have told us about your brother. I mean, we’re supposed to be friends. Right?”
 

Twilight watched as the stallion’s mouth twitched, his movement slowing down a bit. “Well…you see…I didn’t,” he stuttered as a look of hurt entered his eyes. His normal, cheerful tone was gone which told Twilight everything she needed to know.
 

“Is it really that bad between you two?” she whispered.
 

“I think so,” he said slowly. “Maybe worse. It’s…It’s hard to describe.”
 

“What-” began Twilight, only to cut herself off as she noticed Dr. Sparks turning his head. Without thinking, Twilight once more cut the magic flowing into her horn to end the spell as the Tinker looked at the three.
 

“We’re almost to the first lab,” he said with a small smile. “I’m sure you’ll find it quite fascinating.”
 

Before Twilight could open her mouth, Overkill snorted. “I doubt that,” she muttered.
 

-x-
 

Overkill’s eyes sparkled within the lab, her wings fully erect as her mouth hung open to allow drool to touch the floor. The lab they were in was large, nowhere as massive as the tower where Wild Theory worked yet smelled more like cooked meat than of oil and grease. If Twilight had to guess they could squeeze the barn at Sweet Apple Acres inside this room if they were lucky. Metal pipes lined the walls like wallpaper, almost fading into the background if it weren’t for the pressure gauges that were close to the red or the ones that had the skull and crossbones logo on them. Here and there were piles of metallic scrap, probably parts from past failed experiments that they hoped to reuse or scrap along with massive work benches with tall backs. Hanging from the ceiling were long tubes that looked like they were supposed to connect to something as well as plenty of metal chains that had heavy metal hooks at their ends. Some of these hooks were empty while others had metal pipes and other parts attached to them. In all honesty, Twilight was glad she didn’t see any auto-limbs on the hooks for they might play with her mind.
 

Then there was the device sitting in the middle of the room and making Overkill drool. It was large, standing twice as tall Princess Celestia and twice as wide. Its shape reminded Twilight of two saucers placed on top of each other, starting out narrow at the top and widening as it got to the middle before narrowing again at the bottom. The outside was made of bronze, but cleaner and more polished than most of the machinery in which Twilight had become accustomed to around here. Its surface wasn’t smooth however, with many bolts on it to show where the sheets of metal had been attached, handlebars used to open up sections, furnace grates, pressure gauges, and more. The princess also noted that there were several tubes on the upper section that ran across the floor and into the pipes lining the walls, creating a slight hissing noise. The bottom portion was not bare either, for it had a number of gears sticking half out, spinning rapidly as the machine let out a hum that caused her fur to stand up slightly. Around the machine were several tinkers, several of whom were wearing the same spider like attachments that Wild Theory wore when they first met.
 

One of these tinkers stood several feet away from the machine. In one hoof she held a weapon very similar to that of a blunderbuss, only the tubes coming out of the back did not lead to a saddle bag but instead the machine. Twilight could see the tube connecting to a spot next to several gauges. Finally, Twilight saw something else only this made her feel more uncomfortable. It was an object that looked like a thestral with its fur missing. Its ‘skin’ was slightly transparent, allowing her to see the red colored guts on the inside as well as all of its bones in the greatest of detail.
 

“Princess Twilight Sparkle,” began Dr. Sparks as he approached the thestral holding the weapon. “Allow me to introduce you to Dr. Voltage, the leader of this fine experiment. She has been hard at work on this endeavor for the military for the last four years.”
 

“Pleasure,” said Dr. Voltage in a short, but polite tone as she shifted the weapon in her hooves. “Real exciting day this is. Finally got the old gal working a couple of nights ago. She’s-”
 

“It’s a lightning gun!” shouted Overkill, unable to control herself any longer. There was a look in the mare’s eyes that reminded Twilight of Pinkie Pie whenever she found herself looking at one of the Cake’s latest desserts, making her take a step back as her guard flew over to the machine. “By the Storm, it’s almost exactly like how the pulps described it. Finally! I can shoot rebel scum with actual lightning!”
 

Twilight looked at the machine as a shudder ran through her body. “I thought the technology already existed that allowed thestrals to shoot lightning,” she said, her thoughts turning back to Arms Dealer and how he sent small bolts of lightning at her from his bowler hat.
 

“Well, in a sense there is,” said Dr. Voltage as Overkill landed back on the ground, a bounce in her hooves as she smiled at the doctor. “What we have been able to do in the past is create very small currents of lightning. Nothing that would seriously harm anypony, just knock them out. But tonight we are making a huge gallop forward! While some of the more foalish out there believe they can capture actual lightning, my brilliance has taken on the more plausible route of expanding and perfecting the science. Not creating a tiny, insignificant spark but something far closer to the glory of the actual force itself. With this machine anypony can harness that power to destroy their enemies with the ease of pulling a trigger.”  
 

“I think something like this was the plot of a Power Pony’s comic,” said Spike as he walked up to the machine, a hand on his chin. “One of Zapp’s enemies from the golden age tried to make a comeback by making a machine that would create lightning more powerful than Zapp’s. Spent three issues building it up, talking about how it could level buildings with a single blast. Pity the end was a letdown with Zapp taking the machine down with one bolt and the bad guys ending up with a whopper of an electrical bill.”


“I don’t know what a ‘comic’ is or any of the ponies you spoke of,” said Dr. Voltage as she gestured to the other ponies. At once they began to get to work, turning knobs on the machine and recording the information on the gauges. “But I can assure you that this machine is not a ‘letdown’. Goggles on everythestral.”
 

Nodding, Twilight slid the goggles on her forehead down to shield her eyes while handing a pair to Spike. As the young drake put them up, the machine began to hum louder than ever to the point where it almost hurt Twilight’s ears. The gears began to spin faster than ever before with steam escaping from the cracks of the machine. A few spots began to glow red before turning into a bright orange, as if a great heat were trying to break free of its containment. Twilight could see the gauges going into the red, making her fear that there could be an explosion.
 

Before Twilight could put up her shield, Dr. Voltage pulled the trigger on her blunderbuss. Twilight could feel the hair of her mane and coat stand up as a white, crackling bolt of electricity went flying across the room and hit the dummy. Everypony (and dragon) watched as the area that was hit became scorched, the insides expanding with some organs exploding as they were cooked. The energy instantly traveled through the dummy’s body, causing it to jerk. ‘Blood’ escaped from its innards and made its way up the dummy’s throat where it began to spill out. Then, a moment after the trigger was pulled, it stopped.
 

Overkill let out a squeal of delight as the humming died down. “That is the most amazing thing I have ever seen!”
 

“I am glad you think so,” said Dr. Voltage with a small smile as she set down the blunderbuss as it began to smoke. Taking a breath, Twilight found that the scent of cooked meat had become ten times stronger. And she had a feeling she knew why, causing her stomach to turn slightly. But before she could place a hoof or wing on her chest, Dr. Voltage began to trot over to her. “Of course, we are interested in what our new princess thinks as well.”
 

“It is an amazing achievement,” said Twilight honestly, yet slowly. She did mean that. Normally it was the pegasi who put the lightning in the clouds. How they did that was a trade secret which the residents of Cloudsdale carried close to their chests. There were also a few unicorns who could fire mini lightning bolts from their horns, but since those were more draining than normal magical beams and varied in effectiveness they were seen as more for show. So to see another race produce their own lightning like this was an accomplishment to be sure. It also made this feel so unsettling. These thestrals had managed to create something so amazing, yet it was only done so they could find another way to kill each other. In a new and more horrific way.
 

This experience still made her sick to her stomach. Twilight was no filly, she had seen soldiers practicing with swords and spears on dummies whenever she went to visit her brother. Knew what those blades could do if they had used them on real ponies. Just like how she knew what a magical blast or any other spell could do to another. Like with the guards, fillies and colts had done target practice with their spell; sometimes on a target and other times on a dummy. While she knew what they were doing, it was never as real as this was. To see the actual damage it could cause was disturbing. Less so than seeing the glee around her and the pride these thestrals took in this victory.
 

Twilight didn’t like it. No, not at all. She wanted to end this project right here and now. Or, at the very least, have them find another way to use this machine without making it into a weapon of war. Yet with just a glance, she could tell that both Dr. Sparks and Blood Moon were eager to hear her continue. She could see the look of excitement on their faces, hoping for more praise. The last thing she wanted to do was slight them right now, making the rest of her trip here more difficult. She was on mission! Plus there was a chance that the military might be interested in this later down the line. Unless she could come up with a good reason to dismiss this machine, General Steel Trap would voice that she was not fit to rule and all of her hard work would have been for nothing.
 

Thankfully, she had two advisors on hoof that might help with that.
 

“However, I do have some worries about the safety of this machine. Dr. Theory, your thoughts on the matter?” asked Twilight as she turned to the thestral next to her. All of the tinkers in the room turned to heads to look at Theory as the stallion placed a hoof on his chin. Slowly he approached the machine, examining it bit by bit until he had circled it twice.
 

“I will admit that I am more than a tad, tad, tad worried,” he said at last, approaching a tinker with a clipboard and holding out a hoof. Said tinker understood what he wanted on the spot, hoofing over the notes that had been taken. As Theory continued to speak, his eyes roamed over the notes. “I share the Princess’s concern as I thought for a moment that it was about to explode. Unless you were making a bomb, it wouldn’t be useful out in the field.”
 

“But, as you saw with your own eyes, your fears were misplaced,” said Dr. Voltage shortly, a slight huff in her voice. “The weapon handled itself perfectly.” Dr. Theory however shook his head.
 

“I’m afraid these notes say otherwise,” he said simply as he gave the mare the clipboard. Once his hoof was free, he gestured to the machine. “As the Royal Scientific Advisor to the throne, I feel it is my duty to commend you on such an achievement. The hard work of you and your fellow tinkers is simply a tribute to what we can accomplish. This weapon could be the first stepping stone towards a new age. But with that said, there are problems that make it impractical as it is now as well as unsafe. If I were to just go by these notes, you have had fifteen successful firing demonstrations of this device. During that period of time your tinkers had to replace the pressure gauges four times in order to get a more accurate readout. There were also multiple notes of having to replace melted gears, cracked pipes, and other internal components. Perhaps due to the extreme amount of heat, pressure and stress put on it. Not good, not good, not good. I fear that this lightning gun of yours might be too powerful for its own good. We may have to put it on hold until we are better able to contain that level of power.”
 

As Wild Theory spoke, Twilight noticed Overkill out of the corner of her eyes. The battle loving mare was no longer as giddy, looking at the machine with keener attention. She started looking at the machine’s underbelly, sniffing it slightly before pulling her head back and sticking out her tongue. Twilight then watched as the mare gingerly touched one of the gears before pulling her hoof back as if she suddenly saw a snake poking its head out. Overkill shook her head before bringing her hoof over to touch the surface only to pull back right before making contact. With a snort, Overkill trotted over to the blunderbuss laying on the ground where she then picked it up.
 

“That is very short sighted of you, doctor,” said Dr. Voltage, her voice becoming a few dozen degrees colder as she spoke. “As far as I can see, the reason we had to replace those parts is not because of my brilliant design but rather due to poorly constructed parts. No doubt made on the cheap which escaped my notice at the time. In the last four tests, we have not had to replace anything so-”
 

“Hey doc, got a question for you,” interrupted Overkill as she held the gun up in her hooves, looking down its barrel. Everypony turned to look, seeing a small trail of smoke coming from the blunderbuss. “How long until this lightning gun can fire again?”
 

“We have seen that, with everything properly fueled, it can fire once every three minutes,” answered Dr. Voltage.
 

“It takes time to build the power and then compress it,” added one of the other tinkers. “When the weapon fires, it releases all of that stored power. We were hoping to add another lightning tank to this design in the near future so that it can fire twice. Or a way to cut off the flow of lightning before the tank runs out.”
 

Overkill didn’t look too impressed as she set down the barrel before turning to look at the rest of the machine. “I don’t see any wheels or auto-legs on this thing. Were you planning on having the soldiers carry it on the battlefield?” Despite her even tone, all of the tinkers looked like she had just smacked them hard upside the heads. Some found something interesting on the floor while those with notes began to examine them closely.
 

“Well…that’s a later part of the design,” Dr. Voltage said after a moment, a mixture of embarrassment and anger in her tone. “We needed to ensure that the weapon worked properly before we moved on to its mobility.”
 

Overkill shook her head. “Mobility is one of the key elements with any weapon,” she stated. “It doesn’t matter how bloody powerful the weapon is if you can’t get it on the battlefield or hit anything with it.” Overkill then pointed to the line connecting the machine to the blunderbuss. “I can already tell that won’t go to the backside of that machine. Meaning it has a serious blind spot. And with it being that big and heavy, any soldier using it will be nothing more than a target screaming ‘please hit me’. Made worse if this thunder blasted thing really does need fixing every hour on the battlefield! Might be better as a bomb, just drop it from a zeppelin and be done with it all.”
 

“Well,” said Theory as he stepped closer to Overkill. “I guess we could see if we could install it into a zeppelin or just build a vehicle around it. It would help solve the mobility problem and offer some protection. But the problem would be how much power is drained just so it can fire. Might make a mess with the other systems.”
 

“That’s only if they could get that thing to work properly,” grunted Overkill. “If you're right and this thing needs fixing every couple of times it fires, it would just become dead weight. Standing there with its mask off, coughing up a storm so that the enemy has something easy to fire at. Might as well just shoot it ourselves and grant it a mercy death.”
 

“Hmm, as far as I can tell right now the best fix would be for a slower build up,” commented Theory as he looked at Overkill. “If there was a slower flow, it might reduce the stress and heat placed on the machine allowing for it to function longer without needing so many repairs. But that would mean a longer wait time before shots. How long, well it would be hard to say. Ten minutes? Half an hour? A full night? Tests would have to be done to determine the safest pace, but by your account that wouldn’t make this machine any better.”
 

Twilight felt herself smile a little at this as she watched Overkill nodding in agreement. Twilight had been worried that Overkill’s recent anger at Theory and love of things that could, well, kill others would have caused her to defend this machine to the bitter end. Even if only to spite him. Instead, she was acting as though she were one of Twilight’s military advisors giving her own input on how this machine would handle on the battlefield. It made her feel good to know that, despite whatever issues these two had with each other, they put their country first.
 

“Now hold on, both of you!” growled Dr. Voltage, her angry temper evident in her voice. But if it was made to intimidate anypony, the only ones who shrank were the other tinkers. Both Overkill and Theory stood there looking back at the mare who was now foaming at the mouth. “Try to understand that this machine is the future. If your little minds cannot comprehend the greatness of this then-”
 

“Dr. Voltage,” said Twilight in a calm tone.
 

“WHAT?!” shouted Voltage, wings extending as she turned to look at who had spoken. A moment later it had sunken in on who she had just screamed at for she instantly folded her wings back and tried to make herself look smaller. “Princess…I, uh…”
 

Twilight, for her part, glanced at the other tinkers who were still cowering in fear before returning her attention to Dr. Voltage with an eyebrow raised. “I do hope that this is not how you act when other ponies criticize your work or point out a flaw you overlooked,” she said in a firm tone. As she spoke, Twilight did her best to imitate the stance that Princess Celestia would have taken. Her wings were slightly raised to her side while trying her best to seem taller. This was a little harder for her to do since she was nowhere near as tall as the sun princess and that Dr. Voltage was just a tad shorter than she was. Still, her stance did seem to have some effect on the short-tempered doctor as she shrank just a little more.
 

Rather than speaking further to Dr. Voltage, Twilight turned to Dr. Sparks while folding her wings back to her side. “I believe I have seen and heard enough,” she said in a firm tone. She then paused, considering if it were best to leave it like this before speaking again. “The accomplishment of the tinkers here at the Underbelly will be noted. I do hope that both you and Dr. Voltage will take in the concerns that have been brought up if you wish to continue with this project.”
 

“Of course, Princess, of course,” said Dr. Sparks, with a bow and no signs of irritation or obvious anger in his voice. When he rose, what she could see of his face told Twilight that he, at least, had taken their observations to heart. Or at least better than Dr. Voltage, whom she would be keeping an eye on.
 

After saying their farewells to the tinkers, Dr. Sparks led Twilight and her company out of the lab. Overkill quickly moved beside Twilight, shooting one last look of disappointment at the machine that almost made Twilight smile. Wild Theory just let out a sigh as he took up the rear while Spike raced to position himself between Twilight and Overkill. As the group moved out of the room, Twilight spotted Blood Moon standing by the door. He was eyeing Dr. Voltage with a look of utter disdain before he too turned to leave. How Dr. Voltage felt about that, Twilight had no idea, for she was out the door without a chance to look back.
 

“I am so sorry that disappointed you so Princess,” said Blood Moon quickly as he moved to the opposite side of her where nopony was. “The shame I feel right now is truly indescribable! When I had last come here to donate my grits, I was told by Dr. Voltage that the project was nearing completion!”
 

Twilight didn’t answer right away as she looked at the soon to be duke. His voice was slightly panicked while sounding apologetic. To a degree, Twilight felt like she understood why. He was a backer of the Underbelly Academy and had no doubt sunk a large amount of grits into its projects. He clearly wanted to show off what had been done with those grits hoping they would dazzle everypony around. To share some of the glory that the tinkers had achieved with his financial help. Yet, the project he had helped back did not receive the praise he had hoped for. Given the state of Thunder Valley, he probably thought that she was going to lash out at him for wasteful spending or for not paying enough attention to what was going on.
 

Yet there was something that still didn’t feel right to her. Maybe it was the look he gave Dr. Voltage along with not even bothering to come to her aid. Given how much he had given the academy, surely he could have defended her a little. Or…or maybe he was only to have Dr. Voltage dig her own grave by insisting that there were no faults to her machine. Still…
 

“It’s quite alright,” said Twilight, letting go of this feeling for the moment as they walked down the hallway. If he was going to be taking over for his mother one day, Twilight believed that they should get on the right hoof at the start. So she added in as friendly a tone as she could, “It was still an impressive display. But I would suggest keeping a closer eye on things like these. A bit more documentation never hurt anypony.”
 

“Speak for yourself,” muttered Spike.
 

-x-
 

For the next several hours, Twilight was shown around the Underbelly. For the most part, they passed by wooden doors with windows in the upper section that led to the classrooms. It was honestly very interesting for Twilight to peek in and see all the different ways that thestrals here were taught. Some classrooms were small, only allowing ten students inside in what looked like tiny auditoriums. In those rooms the desks were made of metal, bolted to the ground as the students took hurried notes as their professor lectured on the ‘stage’. The professors had no desks in these rooms nor did they employ any sort of blackboard. Instead, coming from the ceilings were spider like appendages that carried a variety of tools at their ends. One of those legs, Twilight noted in horror, had items that looked like riding crops and small blunderbusses like the ones Overkill had. And after seeing one student who had one of his legs bandaged, Twilight wondered if they used a more medieval system of punishing students here. She never saw anything to back up that thought or else she would have busted down the door in an effort to save the student. Instead, each professor had some sort of device in which he or she was in the middle of explaining to the students.
 

Other rooms, Twilight found students working on projects. In one of these rooms, Twilight saw a group of twenty thestrals who all looked to be no older than Apple Bloom or Sweetie Belle. Each one was seated at their own personal work bench as a professor walked up and down the rows, their eyes focused on the task at hoof. From what she could see, nopony there said a word or was looking around, just keeping their eyes down as they worked to assemble something. What it was, Twilight had no idea but it seemed pretty advanced given how complex some of the parts were. Once or twice, there were slight change ups where students grouped up at a long table. But those times were when they were cutting up a corpse in order to better study their insides or learning how to attach an auto-limb.
 

It was at one of these rooms that Twilight found something rather shocking. There the professor had stopped his patrolling to stand in front of a bench belonging to a filly with a cutie mark that looked like interlocking gears made of white clouds. She wore a yellow shirt with brown stripes along with a brown vest made of faux leather over her ashen grey coat. Her mane was black with twin white stripes that reminded Twilight of a skunk, slicked up so that it covered one of her eyes. From what she could tell, and she could have been wrong, the filly was having trouble with her work. At least that’s what Twilight assumed since she seemed so far behind the other students with hers being much smaller. When the professor picked up the device, Twilight thought he was going to examine it and tell her what she did wrong. The truth was far different. In a flash the professor flung the device onto the floor, veins appearing in his neck as he proceeded to scream at the filly and pointing a hoof right in her face.
 

“It’s how they learn,” was all Dr. Sparks said when Twilight brought this up.
 

For a moment, Twilight and Spike looked at each other before she turned to look at the filly once more. At that moment, Twilight wanted more than anything to go in and stop this from continuing. Taking several deep breaths, she thought about how easy it would be for her to do so. She had the power, right? However, as she continued to breathe, Twilight’s thoughts returned to the matter at hoof. The reason they were here: to find out what had happened to the corpse of Midnight Oil as well as the disappearances of foals in the city. Right now, Dr. Sparks was showing them around without any trouble and she wanted to keep it that way for now. At least until she had a better idea of what was going on.
 

So, with a sigh, Twilight continued to walk down the hallway leaving the filly to her fate. However, the purple princess made a mental note for herself. Once she got back to the capital she would be reviewing all the laws that were supposed to protect fillies and colts. And if there weren’t any she would make sure that there would be some in the near future.
 

After moving past that unsightliness, Twilight began to see more of the projects that were in development at the Underbelly. Most of them were being headed by tinkers who had been at the academy for many years or by students who had proven their skills. The room sizes they used varied from project to project, some no larger than the bedroom she had back at the old library while others were simply massive. In the smaller rooms, Twilight usually found one tinker working on a project all by him or herself. Nothing that really stood out for Twilight given their incomplete nature.
 

The larger rooms were something altogether different. In one room, Twilight found herself looking at a boat with legs! The boat reminded Twilight of a large yacht, able to hold a dozen ponies with four steel legs. On its front were two large cannons while on its underbelly was a glass dome. A thestral tinker sat in that dome on an armchair, holding a mock blunderbuss as the dome twisted left and right. In the room after that, Twilight was glad to see that it wasn’t a weapon at all. Instead it appeared to be a set of bronze chairs spaced several feet apart from each other and attached to a massive machine that filled the entire back of the room. The main body of this machine was smooth with only a hooffull of gauges near eye level, along with a row of levers. Most noticeable was an indent placed halfway between the two chairs where a weird light was emitted. The light seemed to shift at random, at one point being a light green, then a sickening yellow, followed by a dark red that almost seemed impossible. Something about it sent a shudder through Twilight’s body as it didn’t seem right. Why she felt like this she couldn’t quite place. Forcefully, she turned her attention to the twin chairs where she found that they had straps on their sides, as if to keep a pony on them against their will, with headsets above each. In a way, the headsets reminded of the one she used on Pinkie that one time when she was to figure out Pinkie Sense. Only this one had attachments that looked like drills ready to bore into a pony’s skull with wires coming out the opposite end.
 

“Impressive, isn’t it,” said Dr. Sparks as they all looked through the window. “This is our prototype lie detector. Still in the testing phase.”
 

“Ah, is it supposed to look that big?” asked Spike with a gulp, his eyes moving towards the drills. “Or scary?”
 

Dr. Sparks merely chuckled at this. “Would give the incentive to tell the truth right away, wouldn’t it? Now, come along.”
 

From there, the group moved down the hallway to a railing which overlooked a massive dark room. On the floor of this room were at least a hundred eggs made of black metal evenly spaced apart from one another. Metal pipes ran across the floor in so many directions that they often overlapped each other, attaching themselves around the bottom of these eggs. Thick heavy bolts could be seen sticking out of these eggs as well in four straight lines as well as several gauges. Then, near their tops, were glass windows that emitted an eerie green light that gave the room an horrific feel to it. As Twilight watched the thestral tinkers walk from egg to egg she could feel Spike holding onto her hind leg while shaking slightly.
 

“What are those?” asked Twilight as she looked over the railing. Out of the corner of her eye, she could see Overkill looking just as clueless as she was. In a small way, it made her feel better. But what dashed that was the equally puzzled expression on Theory’s muzzle. To have her most trusted tech advisor in the dark as much as she was, well, was unsettling to say the least.
 

“Those are our preservation tanks,” said Dr. Sparks as his lens changed automatically to fit with the lack of light in this room. “One of Mad Theory’s latest creations. Come, let me show you.”
 

With that, Dr. Sparks led the way down to the lower level by opening his wings and gliding down with Blood Moon right behind him. At first, Twilight hesitated for a moment, looking to Overkill, who gave her a reassuring nod and showed her that her blunderbusses were at the ready. Taking a breath, the purple alicorn placed Spike on her back before heading down as well, with Overkill right behind her. As for Wild Theory, due to his crippled wing he was forced to take a nearby ladder.
 

Once they were all on the ground floor, Dr. Sparks pointed towards the nearest tank and gestured for Twilight to take a look. Briefly, Overkill nodded to indicate that she would be beside the princess the entire time. Feeling a little bit better, Twilight set Spike down as she approached the tank. With each echoing step she took on the metal floor Twilight’s sense of dread grew tenfold as a nameless fear took hold of her. She chastised herself for this since it only looked spooky, yet still her heart was racing faster and faster where it reached the point where the sound was pounding in her ears. Finally she reached the tanks and looked through the window…
 

And screamed.
 

“What is going on?!?” cried Twilight through her wails of horror as Overkill got besides her, still looking through the window. Inside was a thestral, suspended within a green liquid. Lightly it bobbed within the tank and, for a moment, Twilight thought she saw the slight movement of the eye under the lid as if this thestral were just in a deep sleep. Backing away, Twilight began to take deep breaths as she did her best to reason this out. That thestral had to be dead, there was no way anypony could still be alive with their lungs no doubt filled with…with whatever that stuff was!
 

“Is something wrong princess?” asked Dr. Sparks in a concerned tone.
 

For a moment, Twilight thought about lying to him. To tell him it was nothing or something to that effect. But that idea was quickly shot down as she knew he would not believe her. Not after that outburst. “I…I thought I saw that thestral’s eye move,” she said. “But, that can’t be.”
 

Dr. Sparks nodded gently. “I see,” he said before pointing at the pipes at the base. “Princess, do you see those pipes? They are constantly exchanging the chemicals within the tanks at various speeds. Sometimes powerful enough to give the illusion of movement. A twitch of the lip, movement of the leg, or even putting pressure on the eyelid to make it look like the eye has moved. It can seem unsettling the first time it is seen.”
 

“But what about-”
 

“There’s a pony in there?” asked Spike as he moved over to the tank. Twilight watched in horror as Spike began to climb his way up the tank, almost digging his claws into the metal in order to make his way up. Thankfully, before Twilight could get her wits back to use her magic, Overkill had grabbed Spike by his tail and dropped him to the floor. “Hey, what’s the big idea?”
 

Overkill looked down at Spike as he pointed an accusing finger at her. “Don’t want you to be giving the princess anymore trouble,” she said.
 

“What?” shouted Spike as he got to his feet, looking angry now. “What’s that supposed to mean?!”
 

“Who is making all that damned noise!” came a loud voice. “In my lab no less!”
 

As a figure approached, Twilight felt another scream trying hard to escape her throat yet she managed to keep it at bay. Spike was not so skilled, yelling as he ran back to Twilight and hid behind her. Not that she blamed him as this was the most nightmarish stallion she had ever seen. Large scars could be seen all over the stallion dark brown coat, with gear shaped metal infused into his chest like stitches covering some of the scars as if they were there to keep them from opening up. Maybe if he wore a shirt like so many other thestrals it would have been less noticeable, but instead he wore a ratty grey vest with two pockets. Covering his yellow eyes were goggles, but even with those on Twilight could see one of his eyes was larger than the other and seemingly unblinking. The rest of his muzzle was scarred and deformed, twisting slightly to the side. But worst of all was his back past his wings as it was all made of auto parts! It was monstrous things made of black metal and with exposed belts that turned constantly from his back to where his tail was. Thick, bulky black legs that reminded Twilight of cinder blocks that somehow bent as they spewed out globs of oil and hissed with every step he took. Of course, due to this stage of mechanization, he didn’t have a cutie mark. Only a temperature and pressure gauge filled that spot.
 

This new thestral looked at the group of ponies before him with unkind eyes which narrowed severely when they fell upon Wild Theory. “You,” hissed the stallion. “Why in thunder are you here?”
 

Wild Theory gave an award-winning smile as he waved to the stallion before him. “Hello, hello, hello brother,” he said.