“Did you really need to include that?” Twilight yelled at the Tantabus.

“It’s,” babbled the Tantabus, “it’s a perfectly normal th-”

“It is, but that doesn’t mean I want to see it from out of nowhere! Sweet Celestia, if I saw any more, I’d have to take bleach to my eyes and scrub out my retinas! Ten whole gallons of it!” Twilight shuddered. “Seriously, that’s private. The least you could’ve done is warn us.”

“I don’t have complete control over dreams,” said the Tantabus quickly. It shuffled backward a foot. “I can affect them in certain ways, push them in certain directions, stick objects here or there, but, but it’s not like I’ve got a control panel to affect every single aspect of one, especially with the dreamer herself. I didn’t know that would happen.”

“You are a month old,” mused Luna, “and yet you react to that like… this.” She squinted at it. “I can only imagine where your intelligence came from in the first place.”

The Tantabus shrugged. “Dunno. I just know that once upon a time, I… was. And before then, I wasn’t. Don’t ask me when that time was, I couldn’t tell you. Maybe it was when I finally realized you were my mom.”

“When you were working with it,” Twilight asked Luna, “exactly what kinds of magic did you do on it? Maybe you, I don’t know, put some of yourself into it?”

“If I did, it was unintentional. But magic is a strange thing. It is possible that my magic carried some… imprint of intelligence that the Tantabus filled. It obviously knows things that I never taught it directly.”

Memo to self, Twilight thought. Does magic carry signatures of some kind beyond the obvious?

“Or perhaps it is some combination of what went in,” muttered Luna. She began pacing. “I gave you the capability to see someone’s pleasures and pains, to sort through them, to identify what would work best, and that is merely the start… I suppose that could cause something to happen to give you a mind, theoretically. And I worked with you for your whole development, while I simply cut the previous Tantabus loose and gave it free rein within the bounds of its instructions. If you were even remotely impressionable, that would likely influence you.”

“Are you trying to psychoanalyze me?” asked the Tantabus. It shuffled its hooves. “Please don’t psychoanalyze me.”

“This is important,” said Twilight. “We don’t want to have any more surprises. You’re good so far, but is that something in your creation that’ll always come out, or did we get lucky?”

“Oh.” The Tantabus looked down at its hooves. “Okay, I can see that.” It paused for a moment, then looked back up. “Are you sure this isn’t just some wild goose chase? That you won’t just be running around in circles trying to figure out what makes me me?”

“This question has not been properly solved for ponies, to be honest,” said Luna. “There are many, many arguments on both sides of nature vs nurture. And I am not even certain which side you would fit on.” She rustled her wings in thought. “I cannot remember every precise step I did to create you, so I cannot replicate the process or record it. The broad strokes, certainly, but not exactly, and even the smallest differences can yield immense results.”

“So it is a wild goose chase,” said the Tantabus flatly.

“Perhaps. Unless I rip open your head to see what kind of magic is stewing in there.”

The Tantabus gulped and backed up. “Please don’t.” it squeaked.

“I was not planning on it,” said Luna. “But you could be right. We may be able to trace the general paths, based on how magic works, but without any sort of specifics, this is ultimately an exercise in futility.” She cleared her throat. “Then I suppose we should just get to me telling you what I thought of your latest dream.”

“Yeah, we should. So, what’d you think?” The Tantabus wasn’t quite bouncing, but it kept standing up on tiphooves and then dropping back down. “I put a lot of work into it.”

“Well, it was good, in its own way,” said Luna slowly, “as were the others, but on a larger scale, maybe you could do with a little more variety.”

The Tantabus stopped not-quite-bouncing. “Variety?” it asked. “But I’ve got plenty of variety. You did see the dreams I made, right?”

“Not in content, in tone. It is small,” said Luna, “but it’s just… in making dreams… you tend to have an awful lot of…” She paused, searching for the right word. “…camp.”

“C-camp?” sputtered the Tantabus. “Camp? I do not do camp!”

“You kind of do,” said Twilight, rubbing her neck. “I mean, there’s nothing wrong with it, I can see the appeal, but… yeah, you do camp.”

“After all,” said Luna, “you gave Sombra a fancy mustache and a dragon as stereotypical a Trottingham accent as you could muster.”

“What about the last dream? Spy thrillers aren’t camp.”

“Not inherently so. A ballistic missile is one thing. But for the villain to strap a victim to the outside of said ballistic missile simply because of spite…”

“Fine. Be that way.”

“So tone it down. Learn to be slower, more mellow. Not everything needs to be loud and attention-grabbing. But aside from your…” Luna picked her next word carefully. “…flamboyance… you do appeared to have a knack for knowing what ponies want in their dreams.”

“Well, duh. What kind of a dream weaver would I be if I didn’t?”

“And I have not seen anything to imply any malevolence. You just want to make ponies happy.” Luna sighed. “I suppose I had nothing to worry about in letting you go.”

The Tantabus’s ears shot up and its eyes grew big. “So this mean you’re going to let me off the leash? Let me spread good dreams?” it asked quietly. “I can stay in your dream if you want, but I reeeaaally want to get out. I want to make more mustachioed villains and posh dragons.”

“Well, it is…” muttered Luna. “You know I made you, right?”

“Yeah. We’ve been over this a lot in the past hour or whatever.”

“So that feeling you get of wanting to help others…” Luna stared at the ground and shifted her weight. “It, it is not genuinely yours,” she said quietly. “It is only in there because I put it there. I do not think you truly have a choice in the matter.”

The Tantabus blinked and cocked its head. “So?”

Luna looked up at the Tantabus, brow slightly furrowed. “So if I let you out, spreading good dreams will be all you want to do, and not through any choice of your own. You will only want to do it because I force you to do so. And I- I want you to be free, not released to do some job that I make you do, whether through magical compulsion or otherwise. I do not want to give you freedom only to have you brainwashed.”

“…I’m… I’m not sure why this is an issue,” said the Tantabus after some hesitation. “This is what I was made to do. Literally made. I don’t see why I shouldn’t be fine with it, especially because I like it. You’re fine with moving the moon for all time, and the main reason you’re drawn to it in the first place is because you’ve got a picture of the moon on your butt!”

“It is called a cutie mark,” huffed Luna, “and it signifies a pony’s special talent. Mine happens to be caring for the moon. It tells you what one’s talent is, not the other way around.”

“Mom, that doesn’t make it not a picture of the moon on your butt.” The Tantabus turned the side of its rump towards Luna. “Look at my butt. It’s blank. Is that what you’re worrying about? That I won’t like taking care of dreams because I don’t have a picture of a dream on my butt? I don’t need any pictures on my butt to tell me what I’m good at.”

Luna pawed slightly at the ground and flicked her tail. “And that is all well and good,” she said, “but that is not the only thing at issue here. The previous Tantabus attempted to escape into the real world. Do you want to do so?”

“No!” laughed the Tantabus. “Don’t you remember what you told me just a few weeks ago? It’s tight and restrictive out there. It’s too…” It turned to Twilight. “I need a word that says that something stays the same a lot.”

“Static,” said Twilight.

“Yes! Perfect. The outside’s too static.”

“And how do you know that?” asked Luna. Her voice was growing forceful. “Have you ever witnessed the real world for yourself? Or do you just believe what I’m making you believe?”

The Tantabus rolled its eyes. “Mom, you taught that to me so I wouldn’t want to escape. I don’t see why you would lie, so I believe you. And I don’t like the sound of the real world, so I don’t want to get out there. Simple as that. And why would I want to? It’s much more fun in here, and I can’t hurt anypony.”

“It is not that. It’s… I never taught you a single thing, I simply pushed the ideas directly into your head. Had you been a normal pony, I would have been horrified with myself.”

“Yes, but I wasn’t a normal pony. Well, okay, I’m not really a pony now, but you get the idea.”

“But if I ma-”

Twilight cleared her throat. “Luna,” she said, “you need to stop fretting about this one thing. You made it, yeah, but it’s not a thing anymore. It’s a person. But at the same time, it’s not a normal pony, so we can’t judge it only by our standards. You say you forced the idea of staying in dreams into its mind, but it says you taught it to it. Is there really a difference to it?”

The Tantabus wiggled a hoof at Twilight. “What she said. You formed me out of nothing and decided to take the quick route for giving me morals. But now I’m here, and I can think for myself, and I don’t want to hurt anypony, so I don’t see what the big deal is.”

“But the ideas I gave to you,” said Luna, her voice tensing, “they are not yours. You should have your own reason to want to stay in here, not something I artificially planted in your mind!”

The Tantabus groaned and facehoofed. “I really don’t think you’re getting this, Mom.” It turned on Twilight. “You’ve got a house, right?”

“Castle, but yeah.”

“And if you wanted to, you could demolish it and build a new one, right?”

“Yeah.” Twilight began to see where the Tantabus was going.

“So why don’t you?”

“Because I don’t want to.”

“And why don’t you want to?”

“Just because.”

The Tantabus turned to Luna. “See, Mom? Sometimes ponies don’t want to do things just because. You don’t always need a reason to do things and you don’t always need a reason to not do things. You may think your magic is compelling me to stay in here, but the way I see it, I want to stay in here just because I want to stay in here, and not because of something else.”

“So you accept the methods by which you learned,” said Luna. She said it slowly, as if it was more to reassure herself than to make sure the Tantabus got it.

The Tantabus stared at her for a moment. “Yeeeessss! What do you think I’ve been saying this whole time?”

For several moments, Luna was silent, simply staring at the Tantabus. Then she sighed. “If that is truly how you feel…” Her horn sparked and the star fields on the Tantabus shifted slightly. “You can go now. You’re free.”

The Tantabus’s jaw dropped slightly, and it looked around at the doors, twitching a little. Then it yanked its jaw back up and grinned. “You mean it? I can go through any door? Into any dream?”

“Yes. You no longer need my permission to travel. You can go where you wish.”

“Th-thank you,” said the Tantabus. It stepped forward and hugged Luna. “You’ll see, Mom. I’ll make you proud. I’ll make the best dreams anypony’s ever seen.”

Luna hugged back. “If you don’t, you’re grounded.”

The Tantabus ended the hug and pouted. “Mooooooom…”

“If you insist on calling me that,” said Luna, smiling, “I shall act like it.”

“Well, there’s a downside to everything, I guess.” The Tantabus rolled its eyes, but it was smiling as well. It turned to Twilight. “And thanks for helping me with this.”

“I don’t feel like I actually did anything,” said Twilight. She could feel her face getting warm at the thought. Luna had come to her for help, and all she’d done was hang out and watch the Tantabus do its thing.

“You were a second opinion,” the Tantabus responded. “Well, a third one, actually. The tiebreaker. An unbiased look at this.”

Okay, thought Twilight, that doesn’t sound so bad. She still kind of disagreed with it, but she didn’t want to drag this out.

“Either of you, just call if you need me. Now, if the two of you don’t mind, I’ve got some dreams to enhance.” The Tantabus saluted, then flashed through a door and was gone, leaving Twilight and Luna standing alone.

Twilight glanced at Luna. She was staring at the spot where the Tantabus had been, taking long, deep breaths and blinking a lot. Every now and then, she would rustle her wings or flick her tail. “Well?” Twilight asked. “How do you feel?”

“I am not sure,” said Luna quietly. “It is like I have… lost something. I know I haven’t, it is still in here, but… I am letting go of something I’ve cared for for the past month. I watched it grow, Twilight. I watched it grow and learn, and I was never aware of it.” She paused. “I’ve never had children, and I do not think I ever will. Then along comes this, and before I realize what’s happening, it grows up and is gone. And…” She sighed. “I do not know, Twilight. I feel terrible for having treated it like a thing, but I never knew it was anything more.”

“If you feel like that, then you probably made the right decision. Can you imagine keeping it locked up?”

Luna pondered that for a moment. “True,” she said eventually. “It may have enjoyed my dreams for now, but seeing it then as I do now, I do not want to ponder what it may have felt years down the line. Still, I can only hope it keeps its word.”

“You taught it to, right? It will.”

“We shall see.”

“Plus, if it doesn’t, you’ll ground it.”

Luna grinned slightly. “True. Quite true.”

The next night, Twilight dreamed.

She was in a city. Not any particular one, just a city. In front of her stood a library, or the remains of one, to be more precise. It wasn’t a big loss; it had been demolished due to being old and unstable, and all the books had been moved out in preparation for the move to the new building.

Next to her, the librarian was leafing through papers, mumbling as she tried to find something. Then she found it and groaned. “Oh, come on. You gotta be kidding me. No. Not that.”

“What’s wrong?”

“Oh, it’s just… somepony dropped our book catalogue in the mud.” The librarian held up a thick, dark purple book and, sure enough, mud was dripping from it. “Most of it’s fine, but the last part was completely ruined.”

Twilight gasped. “I’m so sorry.”

“Yeah,” said the librarian sadly. “All the books in there will need to be reorganized. But no one will want to look at them, because those’re the history books on magic.”

Twilight’s ears perked up and she whirled to face the librarian, grinning widely. “You need someone to organize books on magic?” she asked.

The librarian nodded. “Yes, and lots of them, from Neighton to Maristotle to Rutherfoal to Copernicanter to Gallopleo to a bunch of others I’m forgetting. Every single one will need to be catalogued and sorted.”

It might’ve just been Twilight, but she thought she heard a heavenly choir singing.

“And whoever does it,” continued the librarian, “will need to read all of them cover to cover, to be properly sure of their contents. But who’s got the time or patience to read, analyze, and organize dozens of books on the development of magical theory across history from all the masters of old?”

Yes, there was definitely a heavenly choir singing.

Twilight was about to volunteer. But before she could, a soft wind blew. In it, she could hear the Tantabus’s voice.

Thank you. For everything.