Starlight knocked loudly on the door to Generosity Two's bedroom, a tray of food balanced on her back. "Maple wants to know if you're hungry!" she called.
"Food? Yeah, get on in here!" Valey's muffled voice called from the other side.
Starlight pushed the door open. The bedroom was dim save for a bright writing lamp over the desk, where Shinespark and Valey sat hunched side by side, staring over reams of papers.
"Why are you brooding in here?" Starlight asked, trotting closer, guessing Valey hadn't even looked up when she shouted. "It's dinnertime, and neither of you have come out since lunch."
"I'm not brooding," Valey said, frowning at a page as Shinespark made scratches with a mouth-held quill. "I'm trying to one-up some scientists."
Starlight walked up beside them, slightly too short to see onto the desk without a chair. Shinespark set her quill down and lifted the tray, balancing it delicately on a corner and allowing Starlight to stand on her hind legs and see.
The table was entirely filled with designs, notes and diagrams, Shinespark's side focused on pony anatomy and what looked like Braen. Valey's was more covered in connected webs and graphs, intersected by abstract doodles. Starlight blinked. "What is this?"
"I," Valey declared, not losing her focused look, "am trying to take all the mumbo jumbo we learned today, make sense of it with everything we already know, and make everyone on the submarine who said this would take years to learn look silly by doing it in a day. We've got a ton of pieces they don't, and I know this is possible."
Shinespark scratched a line out. "And I'm trying to draft a new suit for Meltdown."
Starlight glanced at both of them, slightly surprised. "Really?"
"Yeah. I think we're both stuck, though," Valey sighed. "So hey, food break. What's up?"
Starlight shrugged. "Not much. I haven't seen Amber, Felicity or Jamjars all day. Nyala and Maple are talking, and Gerardo and Slipstream came by to hang out. It's been okay."
Shinespark nodded, her own focus hardly disappearing as she bit into a steamed bell pepper. "Mmm."
"So hey, mind being a guinea pig?" Valey asked with her mouth full. "I wanna see if what I've got so far is actually as simple as I think it is."
Starlight glanced again at her papers. "It doesn't really look like it..."
"Yeah, well that's just the diagram." Valey waved a hoof. "It's like this: us and the Equestrians mean completely different things when we talk about harmony. We've just been confusing ourselves by putting them together. Our harmony is sort of like a thing's life force, I guess? It's the stuff that comes from our cutie marks, the stuff we get from the crystal palace flames, the stuff that makes our species magic and by extension the ship's flight work, because according to Sparky it technically flies by emulating pegasus magic with a machine."
Shinespark nodded, actually being polite with her food.
"It's the stuff harmony extractors extract... or technically borrow, from everyone but you," Valey continued, nodding at Starlight. "Now, Kinmari's idea of harmony, on the other hoof. They've got a ton of classifications and breakdowns they keep going on about, trying to make it more complicated, but I'm willing to bet you they think harmony is anything like ether, which is liquid hope, or emotions in a physical state or something. I bet you if we explored their stuff completely, we'd find a lot more of these substances that should theoretically exist, beyond ether and moon glass."
Starlight flicked her ears. "But they're always talking about physical emotions." Her mind drifted to her black sword...
"Yeah, I think so." Valey bobbed her head. "So as far as that goes, they're completely different. Now, what I'm willing to bet is that they're still super related, because we always find the trees of harmony growing out of the lifestream, and ponies who generate northern harmony also have thoughts and emotions and stuff. And the great thing is that this holds up: remember when someone pointed out way back when that if harmony extractors just borrow harmony from living things, 'cuz it's like a catalyst or something, then maybe the harmony we bottle in the windigo hearts is just being borrowed from the world and the world is alive as well? Well, boom. Maybe the lifestream is literally the world's will to exist. If it's alive, why couldn't it have emotions, too?"
Starlight stared in thought. "Then wouldn't it have other emotions?"
Valey leaned back and stretched. "Willing to bet if you looked in enough places as crazy as deep underground, you might find those, too. Doesn't really matter, though. The point is I have zero empirical data and just explained in two minutes what those dudes think it takes years to understand, and would be willing to bet candy on me being right."
Starlight thought about that for a moment. "I guess all that does make sense. So what do we do with it?"
"With our knowledge?" Valey shrugged. "Feel smug and superior and keep it to ourselves unless we really need their help understanding something as well, because if all that's true it doesn't sound like the world is a place that needs to be messed with."
"So what are you stuck on, then?" Starlight took a bite from the food tray herself, slurping a few noodles with sauce. "You said you were stuck."
Valey shrugged. "Well, I'm happy with that, so I tried tackling the whole thing we noticed with the bracelets and your runes and whatever else that connects to, and I'm honestly one hundred percent baffled. I don't think it has anything to do with harmony and everything else... probably. But there's a ton of stuff that's obviously related and I have literally no idea why."
Shinespark had finished, focusing on eating instead of talking. "We have Herman's weapon and your weapon," she began. "Both can fly. I wish we still had the axe to compare how it felt to use them, but the church took that so we don't. Their methods of control are different, though."
"I think," Valey interrupted, noodles and vegetables dangling from her mouth, "I'd have remembered if Herman's axe was pitch black, and I doubt it paralyzed anyone. But I was sort of more focused on the dude I was fighting than the decorations, so I honestly couldn't tell you if it had that ring of light around the handle or anything else. It was a magic axe, and all that meant was try to keep your head attached to the rest of you."
Shinespark continued. "We also know the flight controls using that band felt exactly the same as my own flying using my cutie mark. But the only common factor across everything is flying. Herman's axe and the gravity machine are definitely machines, and I manifested my mark normally. It couldn't have come from an artificial source. And then we have no idea what your sword is or how it works."
Starlight's ears fell. "I do. Let me get something..."
She trotted out of the room, then shortly returned, carrying her saddlebags with all her dangerous or important possessions. She pulled out the sword, shrunken to a dagger, and then reached into a pocket and popped out a tiny chunk of black metal given to her by Grandpapa, long ago in the Empire. "See these?" she asked. "They're the same material."
Valey blinked, touching them carefully. "Hey, isn't that...?"
"You've seen this before?" Shinespark leaned closer.
"This is that thing from the codger at the tournament." Valey narrowed her eyes. "Bananas, I forgot he gave you that to hang onto."
Starlight shrugged. "Chauncey is dead, so he wouldn't miss it." She showed the chip to Shinespark. "This is a metal that Chauncey made. It involved using Mistvale arts on a windigo heart, and creating it made it so he couldn't talk to dusk statues unless he was holding it, or something."
"Dusk statues..." Valey tapped a hoof in thought. "Didn't the reason those work have something to do with our cutie marks? And how batponies are different from everyone else like that, and how Crystal used them to drain everyone? So maybe there's a connection between this metal and cutie marks?" She glanced at Shinespark's flank.
"I activate this sword by tapping it against my cutie mark," Starlight pointed out. She made the motions, then held up the glowing sword, showing it closely to her friends. In the triangular hole in the hilt, a tiny effigy of her cutie mark glowed and flickered in time with their bond.
Valey sat back again. "Well, bananas. We just learned... again... that these are all somehow related, and we still have no clue why or how."
"Maybe you should talk to Felicity," Starlight suggested. "Didn't she say something about how this sword worked before, during the tournament? I don't remember."
"Eh. Good idea." Valey shrugged. "Honestly, I don't need to know this. It just bothers me and I'm already in science mode, so... you know. We could also pester the scientists to hear exactly how the receiver for that bracelet in the gravity machine room works, or ask Doctor Lost if he remembers where he got that particular barrel, but you know what? I have this really crazy suspicion we'll just learn they're related again and have no clue why." She waved a hoof. "So what about you, Sparky? I took my turn, now it's yours."
Shinespark looked at her, then at Starlight. "You really want to hear about how designing a new suit of armor for Meltdown works?"
"Okay. Why not?" Starlight asked.
Shinespark looked back at her papers. "I know a lot about power armor," she said. "I won't bore you with what I already have worked out. But there are two problems I'm trying to work on: not crushing her under the armor's weight, and adequately ventilating her. I don't have any numbers for how much she can lift or her heat output, but judging from the steam rising from that pool, I'm at least two orders of magnitude off on ventilation capacity alone."
Starlight tried to look over the diagrams, but aside from the drawings that were recognizable as armor parts, a lot of it was above her. "So you need stronger fans?"
"That won't cut it." Shinespark shook her head. "Even if we can get the heat immediately away from her, it would turn the area around her into a wasteland. I also have a suspicion that the stronger she makes herself, the more heat she outputs, so while she could work a full suit like Braen without being crushed, that would just increase the heat that needs to be removed. And heat is difficult to get rid of."
Starlight bit her lip. "But if you could make the suit easier to move around in, you could decrease the amount of heat she needs."
"That's the conjecture." Shinespark tapped her desk. "I have to ask her to be certain, but it could explain a part of how her old one worked. Not all of it, though. She's just floating in a water tank right now, and you saw how much heat she was putting out. That takes no physical effort."
"But you don't have a way to get stronger at all," Starlight pointed out. "And you were able to wear Braen, weren't you?"
"Right." Shinespark nodded. "Braen was mechanized. When I wore her, she would move along with my own motions, using her motors. There are two problems with that. One is control. Because Braen had my cutie mark, we were able to use the link between us to synchronize her motions to mine, working as a team that shared one instinct. For Meltdown, we'll need another way to read her intentions to animate the armor around her."
"Reading intentions?" Valey cut in. "Sounds like a certain bracelet. Maybe our scientist friends would let you reverse-engineer it and we could finally make progress on my problem as well."
Shinespark closed her eyes. "I wouldn't count on it. There should be other ways to track a pony's muscle impulses. It's just a matter of good engineering." She opened her eyes. "Then there's the power issue. Braen was powered by conventional mana energy, which recharged using my cutie mark. But my cutie mark has extremely rare levels of harmonic potential. While it would be nice to do the same for Meltdown, it's not likely hers is as harmonic as mine."
"To be fair, though." Valey waved a hoof. "Wasn't her cutie mark literally modified or given to her by Garsheeva, or something? Maybe she didn't randomly earn one like that, but there's a good chance she has one."
Shinespark exhaled. "That would just be weird."
"Weird?" Starlight tilted her head.
"Have I ever explained to you how unicorn horns work?" Shinespark raised an eyebrow. "Most unicorns', at least?"
Starlight shook her head.
"It's a complicated subject, but the important part is that the energy they use to operate comes from ambient heat in the air," Shinespark continued. "Normally, heat energy is useless entropy. It's just energy that has dissipated, and there's no way to organize it into something concentrated or useful."
She shuffled a single paper on the desk. "But when you apply harmony... entropy undoes itself. Random, chaotically bouncing atoms will seemingly randomly bounce into more ordered structures that we desire... in this case, recharging your horn after you use the energy contained inside. That's where your horn's energy comes from. So can you see the reason I don't like this? Meltdown's cutie mark seems to make her stronger and create incredible volumes of heat. Even thinking about trying to use her harmony as a life form to create usable energy, like Braen did... What's she doing, converting her own heat to more energy? Where is all that energy even coming from? It makes utterly no sense..." She gripped her head with her forehooves in frustration.
"Hey, come on!" Valey protested. "I just spent the last few hours coming up with a beautiful and gnarly explanation that simplifies all the confusing hullabaloo we've been getting. Don't make stuff confusing again!"
"I'm not making it confusing," Shinespark sighed. "Talking about harmony and Meltdown's cutie mark is forcing me to confront the fact that Meltdown's cutie mark makes no sense in the first place, which has always been a problem but I never needed to know how it worked so I just didn't care."
Starlight frowned at the argument. "Well, Meltdown solved all those problems when she made her last suit, so maybe you should just ask her?"
Shinespark shook her head. "I should. The best thing I can figure is that her suit contained some sort of physical harmonic artifact, like Braen and my cutie mark, except not her mark because hers is a problem and I don't want to think about it."
Starlight glanced at the door. "Then maybe until then, you should take a break. You've been in here a while."
"Yeah..." Valey stretched. "Maybe dunking on scientists can wait. They're not even asking questions about the thing I'm stuck on, it's the bit that baffles them I already have figured out. Sparky, you wanna go do something?"
Shinespark leaned over her papers. "If it's all the same to you, I'm not willing to call this a dead end yet."
Valey pursed her lips. "You sure you want to be working instead of trying to do something for yourself?"
"I am doing something for myself," Shinespark countered, her tail swatting against her cutie mark. "Trying to make myself good for something. I don't know if you noticed, Valey, but my cutie mark is about standing up for ponies who can't stand up for themselves even more than it is about flying. I'm glad you can feel good about yourself by laying around and relaxing, but we're not the same in this. And now I've found someone who needs help badly, and I'm one of the only experts there is in exactly what she needs. I can do this. I need to do this. I need to still be good for something."
Starlight didn't need to be a batpony with a sense of emotional smell to feel the determination in Shinespark's voice. "Good luck," she said. "You can do it."
"...Yeah. Do what you need to do." Valey nodded.
"Thanks." Shinespark went back to drawing.
Valey and Starlight stepped out, the batpony closing the door behind them. "She's intense," Valey said.
Starlight nodded.
"And not used to being the damsel in distress." Valey's voice lowered. "All throughout the Empire, she was the one trying to get me back on my hooves. The only other time I've been the one trying to get her back up is when we were in the skyport..." She shook her head. "Eh, just things to think about. Hey, what's up?"
Maple and Nyala were standing in the kitchen, talking. "Valey!" Maple greeted. "You're finally awake!"
"Hardy har." Valey wandered over and grinned. "Having fun over here?"
"Talking about food," Nyala answered softly. "And music. And games."
"I'm learning that I'm not the only one on the ship who knows how to cook," Maple chirped. "So we've been swapping recipes and ideas. Nyala has a lot of experience making bland food taste good, apparently."
Nyala blushed faintly at the praise. "I only really made it good enough for myself, since Valey would eat anything..."
Before anyone could follow up, the door swung open and Amber stumbled in, her coat still visibly wet. "We had," she panted, "the worst day."
Everyone froze.
"Simply terrible," Felicity groaned in agreement, similarly damp and close behind her.
"Are you alright?" Maple gasped, trotting over as fast as her healing ribs would allow.
"Yeah..." Amber whined at the ceiling, collapsed on her back. "We ignored what turned out to be good advice on where not to go for lunch, got into a fight about what certain types of fruit are called, and got kicked out of the bathhouse because the management are prudes. I miss Sycamore's bathhouse in Riverfall..."
Felicity scowled in agreement. "Good grief that mare had an overbearing sense of decency..."
Valey blinked hard. "You guys got thrown out of a bathhouse for inappropriate conduct? What did you even do?"
Felicity glanced at Starlight. "...Best not to say with children in the room, darling."
Amber burst out laughing.
"Ahem!" Felicity snapped. "I'll have you know I was enjoying a tremendously luxurious afternoon, do not mock it, please and thank you very much..."
Amber didn't stop giggling. "Oh, we were the worst, weren't we? This day was so bad..."
"Indeed. Truly a laughing matter." Felicity frowned hard, clearly making an effort not to join in. "I don't suppose anyone could be a dear and bring me a towel? I need to dry off my ego..."