It didn’t feel quite right to call Moonrise a city, in the sense of the places in Equestria that were cities. But neither was it a military camp anymore, since nearly two months had passed since any of them had done anything remotely military. Given the two options, Quill preferred to think of it as a city. It wasn’t a place for soldiers to wait until they fought again—it was a place for them to live, with no more expectations beyond that.
Quill passed through the outer barrier to the central warm core, lit only by the faint light of glowstone brackets along the walls. It was better than torchlight to keep the space lit through their second lunar night, even if it did mean a full fourth of all their unicorns did little more with their work-shifts than recharging spells.
It’s either this, or spend the months in darkness. Bat ponies were good at living in the dark, better than any other kind of pony that had ever lived. But with such large numbers, the constant squeaking for navigation would’ve been confusing. To say nothing of the other creatures in the dark with them. How real bats manage not getting themselves confused with so many brothers and sisters all calling out together, I’ll never know.
Through the thick cloth shroud, Quill stood before the massive metal core. He could feel it even from many paces away, the heat rising from it was so intense that during the day it eventually glowed a dull red in total darkness. Now that the night was nearly over, there was no glow left. In fact, Quill nearly tripped over a pony huddled on the floor near the railing. She wasn’t the only one—the room was packed in tight with ponies, basking in the warmth of the warmest part of Moonrise.
Silver Needle told him that they should all be kicked back to their living areas, that even laying on the floor compromised the efficiency of the heat-exchangers. But Quill didn’t have the heart to send them away. This was the only part of Moonrise that was above freezing. We need more heat, or more metal to store it. But somehow he doubted they would be making another trip to take destroyed tubes from Vanaheimr and making them into a bigger storage.
He took to the air, flying over the tightly packed group of ponies. There was enough room for him to pass, barely. More importantly, stretching his wings in someplace so warm was a tremendous relief, after spending so much time in a barracks no different than the rest. If anything, the problem with the core was unequal access. It didn’t look like the weakest and sickest were getting the warmth they probably needed.
A problem for next night. We didn’t see huge numbers freeze this time, that’s what matters. Our insane plan worked. Quill finally reached the door on the far side, which ponies at least had the good sense to keep clear. He slipped through, then stopped for a moment in the stairwell. A line of ponies stretched up from below, each one tightly bundled in their warmest robes. Yet as he emerged, every one of them rose from where they cowered, soldier and camp follower and ditch-digger alike. “Lord Commander,” they whispered. With honor now, instead of spite.
Iron Quill passed between them, trying to look more dignified than his old body and rickety joints would allow. He did wear a little of the armor at all times, at least the breastplate and the heavy cloak. It made him stand apart from the other residents of Moonrise. It meant that all who saw him had to look a second time, just to be sure.
Currently there were four finished floors, each made from lunar bricks and mortar. They were already encountering trouble with the floors, with at least two reports of the thin-rock sheets they’d sliced caving in under the pressure of many hooves. But without wood, they’d thus far found no better solutions.
Eventually though, he reached the top floor, and the “section” where his own camp was staying. A common room was packed with ponies, huddled around the metal heat-radiator and a ring of glowstone as though it were a fire pit. There were no fires anymore—both on his order and because they’d burned just about every bit of scrap material left on the moon surviving the previous night. Ponies lifted hooves to salute him, though his own stallions didn’t rise the way strangers did.
Where before the ring of tables and chairs around the vent had been spread a good distance away, and ponies had sung and chatted amicably with each other—now everypony huddled on the ground, as close to the vent as they could. The only ponies who weren’t right beside it were doing some chore, cleaning the common room or preparing the next meal of potato-gruel.
Quill passed these as well, sliding a bowl for himself as he turned past the bunkrooms to the single part of his section that no other section had: the command rooms.
“Took you long enough,” Penumbra said from behind him, her voice its usual collected cold. “Where did you fly off to, anyway?”
Quill didn’t speed up, holding the bowl in his wing and eating while he walked. It wasn’t terribly dignified, but these ponies already knew he was only mortal. He was no myth to them. “Making sure… Moonrise is still alive,” he said. “After last month… still have dark visions. The crypt has enough caskets.”
“There aren’t any caskets. We didn’t have time to carve them, remember?” Penumbra rested one hoof on the door to the meeting room, stopping him from opening it. “Finish that bowl. You’ll thank me in a minute.”
Iron Quill couldn’t imagine why, hadn’t she just said he was late for the meeting? But Penumbra’s help had already saved the whole city, so he wasn’t about to start doubting her.
He stopped an aid passing in the hall, offering the mostly-empty bowl. “Dispose of this, soldier,” he ordered, before Penumbra finally got out of the way and let him into the room.
He soon learned why she’d made her suggestion.
In attendance today were the usual suspects in Quill’s council. Sylvan Shade of course, with his knowledge of alchemy and natural philosophy. Cozen, whose ideas had been so useful in the last few months. Chain Mail, representing the armed forces and the ones keeping order in the city. Silver Needle, quartermaster general. Appleseed, newly invited from the camp followers for this meeting specifically. He shifted about on his hooves, constantly uncomfortable. And there was no mystery about why.
In Quill’s own usual spot, Nightmare Moon already sat, settled back on her haunches and looking incredibly bored. She raised an eyebrow as he came in, though otherwise her reclining position was casual. There were no Voidseekers with her.
Penumbra stopped in the doorway to bow, the only one unaffected by the terrible chill in the room. The others all huddled close under their blankets, avoiding the head of the table as though a glance there might light them on fire.
“All this time I’ve wondered the secret to your success—apparently that secret is paying as little attention to your work as possible.”
Quill dropped into a bow far closer to the table, though he didn’t bow nearly as deeply as Penumbra, or stay there for as long. He was the Lord Commander—if anyone wouldn’t be groveling, it was him. “Forgive me, Princess. If I had known you were in attendance—”
“My visit would’ve been wasted,” she interrupted. “I am not here to see a carefully prepared mummer’s show. I am here to see who you really are. This is another of your crisis meetings, yes? I am going to observe my miracle in action.”
And make everypony so nervous they can’t get anything done, he thought. He nodded again, pacing around the table to the empty chair at the other end. It put him right beside the blackboard instead of far from it, but it would have to do. The conference room was bigger than the tent, with an oversized door large enough to permit whatever equipment might be required. Today there was nothing special, just a few tiny trays of dirt near the earth pony, and a few pots of plants that Quill didn’t care to identify.
“Of course, Princess. Your will be done.” He settled in his chair. “I have already kept you all waiting long enough. Princess, I hope you don’t mind if we forgo the constant pauses for respect and honor throughout the meeting? If everypony would get that out of the way now, it would make this easier.”
She nodded impatiently. “I’ve had enough on the way in. Speak as though I am not present. I will not interfere.”
Iron Quill didn’t believe that for one second, but it didn’t matter. They went on with the beginning of the meeting, discussing the state of Moonrise and their expected survival chances. After confirming that no one had frozen to death.
“With sunrise tomorrow, it doesn’t seem likely to happen,” Silver Needle finished, at the end of her report. “The only death so far was during a brawl near the beginning.”
“Forcing different camps to live together is… hard on morale,” Chain Mail said. “We are all struggling to cope in our ways.” His more than many—he was still training a group of former prostitutes and vagabonds to be watchmen. As Quill understood, progress was slow.
“Not for much longer,” Quill said. “We should be able to finish the rest of the structure in the next month. We have many hooves ready to work again. They remember the night of last moon.”
“It would be better if we could promise… a warmer night to come,” Sylvan said. But compared to several of the others, he was less frightened of Nightmare Moon’s presence. At least he’d seen and spoken with her before. “Can we do that?”
“It will be colder if we don’t do anything,” Cozen said, avoiding looking towards Nightmare Moon. “We will have the other two warmth-exchange tubes running if we finish the other wings. They will be spreading the same warmth thinner. Honestly, we may need to develop different customs for living in day and night. Perhaps it is a waste of resources to build the other tubes at all.”
“Mirrors,” Sylvan suggested. “We just need more of them. Point more light at the surface, and heat it warmer. Make the heat last longer.”
“I thought this meeting was about the food supply,” Nightmare Moon said, tapping one hoof impatiently on the table. “I trust you will resolve the issue of insufficient warmth. You’ve already done it, it’s just a matter of degrees. But what will my army eat?”
How long did you let us do things our way? Quill nodded obediently. “We’ll table the warmth issue for the time being.” He gestured towards the new pony. “This is Appleseed. After investigating every camp, I found the pony with the most farming experience was one of my new recruits.”
He might be a new recruit, but otherwise there was nothing new about Appleseed at all. He was older than Quill even, with a gray mane and slightly swollen joints. Even being this close to Nightmare Moon was clearly a strain for him. But at least he hadn’t tried to run away, or collapsed from the otherworldly presence of the dark Alicorn.
“After our last interviews with him, I’ve invited Appleseed back to offer his expertise while we discuss our food supply. Appleseed, you aren’t yet a member of this council, so don’t feel like the pressure of what we discuss falls on you. We’ve brought you for your expert opinion and nothing else, understand?”
He nodded weakly.
“Very good. So we understand the scope of the problem, Colonel Needle. You’ve conducted the complete inventory I asked for, yes?” At her nod, he continued. “Please explain how much time we have to work with.”
She rose from her chair, shuffling with the papers in front of her, before finally settling on one. All the while Nightmare Moon’s eyes focused on her like a lance, never blinking.
“Many of you know we came expecting to besiege the Castle of the Two… the Tyrant’s stronghold. We expected to supply an army much larger than the 3900 who currently survive. But we also expected to be able to salvage from the territory, and to barter with traders. With all of these options closed, we have relied on our stores for the last two months. It also does not help that we did not previously supply the camp followers.” She raised a hoof towards Cozen. “No, I’m not suggesting a change. Just pointing out a statistical fact. We have more mouths, and less ways to feed them.
“We have been draining our stores for the last two months at full rations for each mare and stallion. At the present rate, we have four moons left to us.”
It was the longest deadline they’d ever had for one of the miracles that Nightmare Moon demanded. But it was also the slowest to solve. A cave could be heated or cooled in hours. Growing new food was much slower.
“If we were in Equestria, how would we solve this problem?” he asked, indicating Appleseed. “Could we raise a crop so fast?”
He nodded, glanced towards Nightmare Moon, then started to cower again. When Appleseed finally spoke, it was only with great effort. “With earth ponies to work the soil and pegasus ponies in the air above, you could feed this whole army in under two moons. But forgiveness Lord Commander, we don’t have any of what we would need for that.”
“What do we have?” Nightmare Moon asked. The question was so unexpected that Silver Needle jumped. The princess, actually caring about the finer details of her army? In all his time working the stores, Iron Quill almost never heard her ask questions like that. Only when she was out of wine, or fine soap. Needless to say, she was out of both.
“There are, uh…” Silver Needle shuffled around with her papers again, before selecting a scroll. “Potatoes, carrots, wheatberries, corn, rice, barley, oats. Our supply of luxury produce has all been eaten, though I think we preserved seeds where we could.”
Nightmare Moon waved a wing. “I understand that, I know the slop you try to feed me and call a feast. I am asking what you expect to do to raise crops in this cave? I give no honor to my sister in saying so, but the realities of the plants we know require sunlight, do they not? Glowstone is not enough.”
“We, uh…” Silver Needle faltered, scrambling with her scrolls. “Quill ordered the dung heaps kept in a nearby cavern, rather than burned or dumped outside. And there are, uh… straw? Trays?” She whimpered, looking desperately towards Quill.
That seemed like enough of an attempt that he could help her. “Forgive her, Princess. We don’t yet know what our solution will be. That’s why we’ve invited Appleseed. With every one of these issues, the solution has ultimately come thanks to involving an expert. Appleseed, go over your suggestions again. You know our limitations. Explain what you told us in the last meeting.”
All eyes settled on Appleseed. He shifted in his seat, and spoke to Quill instead of the princess. “O-of course. Well, there’s… everypony knows that not all crops are equal. Obvious… right obvious thing about it is that what we plant can’t go into anypony’s bellies. Planting cuts our supply even further.
“Key to all of this has got to be the potatoes. Right bland they are, but you can feed as many ponies in one acre of potatoes as ten of wheat. Making it taste worth eating after is a problem for the chef. Once they get established.”
“And I think we all agree with you there,” Sylvan said. “You say they’re the easiest to grow, so potatoes it is.”
“They won’t keep much longer anyway,” Needle added. “We’ve already rotated the potatoes through most meals we’re serving in camp.”
“Yes, but…” Sylvan hesitated. “But where is the field? Even if you don’t need much space… we need a fair bit to grow for all these mouths.”
“More ‘an space,” Appleseed added. “Potatoes are a hardy crop, they’ll resist a freeze better ‘an some, but if the soil gets colder than about… this room, they’ll freeze and die. And they need plenty of water, even with love n’ care you’ll need to put an inch on the field by weeks.”
“I could probably cut that significantly,” Sylvan cut in. “My greatest achievement prior to signing up with the rebellion was in helping to colonize dry climates. I learned that precision and water retion can cut the water we use by… three quarters. If we’re careful.”
“And the field will be…” Nightmare Moon began. “Surely you don’t expect me to hold a new bubble of air outside for months at a time, Quill. You could not have forgotten our earlier experience so swiftly.”
“I do not, Princess,” he said. “Finding a place for the field…” He hesitated. “We always knew it would be a challenge. Space isn’t the issue, but… as Appleseed points out, caring for our crops once we plant them is. We must keep them warm, and we must somehow give them light. This limits where they can be placed.” He looked to Cozen. “What can you tell me about lighting them? What is your solution?”
“I…” She hesitated, then blundered through in a rush. “I looked at the magical and the physical. I think a combination of both will be the only way we don’t starve. Obviously the simplest way would be just to let light shine on them. If we use a ceiling of glass, we can let the sun do its work during those parts of the month. Assuming… can potatoes live in constant sunlight?
“I have no idea,” Appleseed said. “Celestia never—the Tyrant never failed to lower the sun before.”
Cozen shrugged. “We could lower a shade if we had to. Regardless, it isn’t the day that is the greatest trial for us. I have—”
Nightmare Moon laughed again, and this time her voice shook the whole room. “Oh yes. Installing transparent windows when the only shelter keeping you alive is the seal of a cave you cannot replicate. Do you know how much force would be pressed against a window, even a very small one?”
Sylvan answered that. “A lot. There is… void out there, and air in here. It would be the reverse of the vacuum vessels I have in my collection. They are each, perhaps… an inch thick.”
“I believe it could be done,” Cozen said. “We would build them in small sections, with steel to hold them in place. Or perhaps set them into the rock directly. A precise application of teleportation and heat-amplification could do it, to melt the rock around the windows. It would require… perhaps… our Princesses’ indulgence to assist. It would be easiest if there were air on both sides while we worked, and only she has the power to hold that much.”
Nightmare Moon scoffed. “So you’re going to make… windows strong enough to hold pressure, then… set them in the stone ceiling with unicorn magic. I assume you haven’t forgotten the sky above your heads is thirty feet of solid rock? How long do you wager it will take you to dig the shaft for each aperture?”
“We, uh…” She looked away, to Quill this time. “I mean, I meant to ask, if we could consider one location primarily for the field. I believe we have no choice but to construct it in the tunnels near the entrance. There we can use our earth ponies to carve down and seal the windows in place. Is that… possible?”
Quill turned to Appleseed. “You lived in those tunnels. Could we grow a crow in the upper section of the entrace there, large enough to feed everypony?”
“I…” He floundered, but Silver Needle was ready. She pushed over their detailed map of the cavern. It included the tunnel entrance. It really was quite wide, and the slope was shallow enough that they might have some distance to place a field.
“Perhaps,” he finally said, looking away from the map. “It will be… a near thing. If we lose even part of our crops to the cold, we will surely starve. And… forgive me, Lord Commander. But you haven’t spoken of the night yet. Potatoes are a mite forgiving of the shade, but not of nearly half a moon without light.”
“Yes,” Quill said. “So let assume for this conversation that… we commit to turning the upper section of this tunnel into a field. We will make hundreds of windows from thick glass, each one small enough to remain strong. I know we have craftsponies among us, glassblowers and sand mongers alike.”
But even as he dismissed it, his mind was already spinning. They were out of oil, and they would need incredible heat to melt the sand. Finding the right flux and making it clear were issues of their own that he didn’t think anypony in this room cared to hear.
“Princess, will you assist with this, if we manage to create the windows, and test that they are strong enough to hold the air?”
“Certainly,” she said. “But you should realize—glass holds back the air almost perfectly, but even impermeable rock is not a perfect barrier. By weakening the ceiling, you are creating leaks. Our air supply will drop, escaping out into the void. There will be… some science to replacing the air with your electrolysis at the rate it is lost. I would suggest an airlock would be a prudent construction in that tunnel, since a failure in it would at least allow these ponies to survive. But given the loss of the tunnel would mean death by starvation, I believe the vacuum is kinder. I would rather my army die in a few minutes than in months of agony.”
Her words hit everypony in the room like a brick, stunning several of them. Sylvan and Cozen were at least used to this—Nightmare Moon’s inscrutable knowledge of things that no other pony could grasp.
Only Cozen was brave enough to ask about any of it. “What is ‘science’? And… electrolysis?”
“Natural philosophy,” Nightmare Moon said, annoyed. “And electrolysis.”
Quill hesitated for another moment, but he hadn’t got them this far by keeping silent. “Are there… Princess. Your knowledge makes us all seem like insects. Is there any you think might be worth sharing with us, so that your army’s chances of survival might increase?”
Now she was the one caught off-guard. Though the Alicorn was older than all of them by far, and faster to recover. “Right now? You’re overlooking an important food source. It was… I considered it in my plans for a lightless Equestria. And you’ve already mentioned to have a significant stockpile of dung so…”
She seemed to be waiting for Quill to finish her thought for her, but he only stared. What did she mean?
“Fungus!” she exclaimed. “Mushrooms. They require little or no illumination, they require only a little rotting matter to grow. Dung mixed with lunar sand, perhaps. The ratio would be yours to discover. Their growth would generate not-inconsiderable warmth as well. I remember…” She trailed off, staring at a nearby wall. “The fungal vats were always warm when I went in. There is a price paid, however—fungi breathe, just as you do. They may require you to melt more ice to account for that.”
“Do we have…” Now even Quill didn’t know. Mushrooms weren’t exactly something he knew anything about. You didn’t fill the rucksacks of marching ponies with something he considered an accessory to expensive cooking. “Mushrooms?”
“Don’t bother,” Nightmare Moon said, raising a wing. “The answer is yes. Speak with my chef, she will give you any that remain. I expect to receive the first harvest personally to replace what I lend you. However—you will not be starting with a supply to have any hope of growing enough, or I would have mentioned sooner. Your plan can only be supplemented while we wait. All these other impossibilities must be rendered plausible, through means I can only speculate. Light most of all.”
“Yes,” Quill agreed. “I believe we’re ready to reach that question. I assume you must have something, Cozen, or you would’ve stopped us before we began finalizing details. If I’m about to ask Silver Needle to design a glassworking shop and divert many laborers to working it, I must know.”
“Of course. I began with our heat-device as a guide. It absorbs sunlight during the day, and shares the heat with us when darkness arrives. I believe, though I admit I have only conjecture for a basis, that the strength of the sun enters into and is stored within the metal. We know from every blacksmith in the camp that there is capacity for more. That said… heat alone will not make a farm grow. I don’t believe we can get anything hot enough to produce sunlight, not by any spell or artifice of craft known to mare or scholar.”
“Thank you for that waste of time,” Nightmare Moon said, folding her hooves in front of her with growing annoyance. “You’re right, by the way. The metal core absorbs sunlight as heat. But your rediscovery of a plainly obvious principle does not grow bread for my table.”
For a second, it looked like Cozen might give up and fall silent again. But Quill nodded her on, and so she kept going, less confident now. “My air-crews are more than skilled in the working of the machinery now, so that they do not require my help. I have been… tinkering with glowstone.”
She rose, making her way to the low cart tucked into one side of the room, and removing a tightly-wrapped bundle from atop it. She settled it on the table, then unfurled it.
It was a very large chunk of glowstone, the size that might be used to light an entire trebuchet-crew while they worked. The glowstone itself, a chalky white mineral etched with thin runes in black paint, had been wrapped in a set of interlocking metal rings, the sort of mechanism that Cozen had been hired for in the first place.
“What does it do?” Nightmare Moon asked, staring at the object. She no longer looked bored.
“Less than glowstone, actually. As our… princess will know, the rocks we use for illumination can be charged by any unicorn. They harvest and store mana, then convert it into light. This no longer has the capacity to harvest from a unicorn—instead, it stores light directly, then can be made to release what it stores at any rate we desire. This one has been absorbing the light of our melting apparatus for the last several days.”
She lifted the object into the air with her magic, then twisted the outer dial. Instantly the white stone began to glow bright red, the same red as the metal coil that melted ice. It wasn’t the cold blue of a glowstone, but bright red, that got brighter the further she twisted.
Light filled the room, harsh enough that Quill and the other bats lifted hooves to shield their faces, momentarily stunned.
It wasn’t just bright. Quill felt himself sweating in his thick robes. Sylvan didn’t need a jacket with his earth pony strength, but Chain Mail tossed his to one side.
A few seconds later, Cozen twisted her dial back, and the glowstone went dark. “I have the spell diagrams here if the princess would like to see,” she said, passing them over. “I won’t show you, Qu-Lord Commander. I know you do not care.”
“I care only that it can be reproduced.”
“Yes.” She nodded eagerly. “Though I should point out that it permanently destroys the glowstone’s original purpose. It cannot ever be charged by unicorn again.
“So you would do… what with these, exactly?” Appleseed asked. “Forgive me for asking, but we don’t often use… strange spells among our crops.”
“We would need to build… mirrors, I suppose,” Cozen said. “One for each of these. If their limits translate as glowstone does, I expect we’ll need several large chunks for the farm, rotated over the course of the night. Let them replenish in the light of the day, and bring them out at night.”
“I can’t help but notice many of our plans involve moving back and forth between the surface,” Sylvan said. “I don’t suppose there’s a way to make that process simpler. Requiring the time and effort of our princess every time we work there seems like… a foolish strategy.”
Nightmare Moon laughed, so loudly that the entire chamber shook. “What a day it will be when you need no magic to walk along the surface of this place. It can be done—but head my advice, and stow that question away for some future generation. You will not solve it. Focus on food.”
She rose, walking elegantly to the doorway. “Begin your work then, Lord Commander. The sand drains from your hourglass. Use it while you can.”