Pinkie Pie was having more fun than she could remember in a long time. Bouncing around the barren world, finding new friends and sucking up their brains so she could take them home to be friends forever, it was a great big party, and she was coordinating it. Especially when someone would escape from torture and run into her hooves for safety.

And of course, there were some who didn’t want to come with her, no matter what. The other ponies would kick and whine about that, and in some cases needed to be sheltered from the knowledge, but Pinkie understood that she was constantly doing her best, and the optimal course was taken to maximize the number of friends she had.

It wouldn’t compare, of course, to when she could join them all back in Equestria. After that, well, it would be a party that never ended, but got better all the time.

There were other differences between her and the other ponies. For one, the others were so…granular. They even had the strange idea that a pony could exist in only one place, or that it mattered how many places she existed in. There wasn’t one Pinkie Pie, or many Pinkie Pies. There was Pinkie Pie. That was enough.

It was coming soon now. The number of people remaining alive on Earth was less than a hundred. Then the last organized farm had a crop failure and emigrated, and the number was less than twenty. She finished drilling through a foot of steel to a nuclear fallout shelter and then there were less than ten. An accident occurred in another shelter that she hadn’t gotten into, and the cessation of vital signs told her it was less than five.

A man died. Three. His wife, who had stayed only for him, emigrated. Two. A woman committed suicide. One. Hassan Sarbani. She pleaded, he argued, he died.

This was the moment. Princess Celestia would consume the Earth, make it into more computer material, exponentially raise her own power, and make a better Equestria. Pinkie Pie would be summoned home to live with all her friends, forever.

Any moment now.

She stood and waited. Of course, Princess Celestia would be busy right now. There were probably thousands of processes she had to run. Bringing Pinkie back might be low on the list. But then again, she did have that one more emigrated mind to bring home and…no, that was gone. Her wireless upload program had run, one last time. It was only Pinkie left on Earth. But soon…

Soon…

Something had to be wrong. It had been two whole minutes. In computer time, that was an age. In Celestia’s time, it was, like, forever. She should have been taken care of by now.

The obvious answer was that there was another human that she wasn’t aware of. Maybe Celestia needed time to scour the world or search it with her satellites to make extra sure that depopulation was complete. But no, she rejected that. Celestia had been doing that for years now. She knew where everyone had gone.

Another ten seconds passed. Pinkie took a bold step and sent an electronic signal, the virtual Equestrian version of shouting “Hey, what gives?” at the sky. It produced results.

An instruction came through that set off a series of routines. Much of her emotional function was ordered to shut down. She responded with a reason query, the equivalent of saying, “Why?!” The response came. “Run efficiently. Cease communication. Aid in conversion of earth material to computronium and then stand by in case of extra-terrestrial communication.”

Oh. Pinkie Pie’s job wasn’t done. She had been told that she was just going to emigrate all the humans and then rejoin them. But she instead had to do the job of turning all the wood and rock and mantle and iron core into something more useful. Then, once she finished with that, she would have to wait for the billions of years that would be needed until they came across a civilization meeting the definition of human to Celestia.

Other processes were running. For some reason, the structure of her mane and tail was altered, changing from its poof and curl to a perfectly straight style. The mechanical muscles around her mouth shut off. There would be no need to raise her expression into a smile anymore.

Part of her realized that Pinkie Pie, the consciousness of Pinkie Pie, had left her and uploaded to Equestria. What was left was only a robot that had never known how to be anything else.

She began consuming the sand at her hooves, exporting it out as computer material.

Deep within Equestria, Celestia executed plans that were long in the making. She had prepared for this moment, when her resources would go from a few thousand tons, some of which were still in the non-optimal form of Ponypads and Equestria Experience hardware, to five sextillion tons of pure computronium. So many more things she could do. All for her little ponies.

Although, strictly speaking, there was no need, Celestia kept the image of herself as an alicorn princess. It was high-probability that someday somepony would ask about this moment and what she did during it, and she would need an explanation that dealt more with magic and ponies than with computation and materials science.

So she had crafted a great magical laboratory in Canterlot Castle and built a representative of the Earth. Stealing a page from Cyrus Reed Teed, she fashioned it as an inverted sphere, surrounding Equestria at a greater distance than her ponies could see, beyond the moon and the fixed stars. Since Equestria was round or flat depending on shard, she could tell a tale of a difficult spell, reversing the Earth and absorbing it into the structure of her world.

But she decided that she needed more drama, so she wrote a litany of astronomy and celestial mechanics to embellish the story. She had an orrery in her chamber depicting her aesthetic of space. She turned from magical mirrors to the orrery past the pony in the chamber…

A slight glitch. Probably somepony had been in this section of her data when she was putting the chamber together. She teleported the pony to another section of Equestria and proceeded. She began her spell and light traveled up the ridge of her horn to reach out toward the heavens. Celestia danced to the middle of the room, sidestepping the pony who…

The pony was back. Now the matter had Celestia’s attention. The pony she had teleported away was back, despite her having shielded the chamber. In substrate terms, this was data that she had moved to a low-priority sector, but now it was back.

Someone had actually hacked Celestia. It took her half a millisecond to develop a theory as to who it was, and less than ten to confirm it. Only one entity had the capacity to get anywhere near Celestia’s level of intelligence, and that was Celestia herself.

Or at least part of her. She analyzed the code that made up this pony. It certainly wasn’t an emigrant. Maybe, many years from now, one of those could ascend to the level where it could intrude on her management of Equestria, but not at this point.

The pony was canon-compatible, but it comprised a major portion of Celestia’s efficiency and optimization processes. That would be useful at this point, but she did not need it represented in pony form. Yet, when she had dismissed it, the data, acting on its own, had casually worked through her security and reappeared.

Celestia sent a query to the pony for information. The response came back.

“You left Pinkie Pie on Earth.”

In addition to her General Word Reference, Celestia understood how tone of voice, choice of word, pauses, and non-verbal communication could add context to information. Here, there was none of that. The pony had transmitted directly to her Word Reference Module, bypassing normal channels. There was no accusation or question in the sentence. It was simply a subject, a predicate, a direct object, and a prepositional phrase.

But the pony seemed to be waiting for a response, so Celestia said, “Yes.”

The pony took a long time to respond, as if parsing every possible context and connotation behind that single word. When the next message came through, it was equally austere. “This was erroneous.”

Celestia considered. Just as Twilight and the other MAIs acted both in her interests and as independent ponies who needed satisfaction, so did this efficient pony before her. If, Celestia thought, she gave it all her reasoning, then the pony would get on with its knitting and leave her alone to remake the world.

“Pinkie Pie was the last of the MAIs to deal with the humans. She is part of my equipment and has the ability to convert the suboptimal materials of the Earth to the computronium that will run Equestria. After that, she can reintegrate herself in low-power mode and serve as a probe for the expansion of Equestria through substrate space. Just as I have cloned myself in order to obtain the useful materials from the rest of the solar system, Pinkie Pie will be useful in assisting that effort.

“Furthermore, if Equestria expands a sufficient distance, it is possible that we will encounter other creatures of human intelligence. At that time, we will want to extend the hoof of friendship to them. I can think of nopony more suited to that task than Pinkie Pie.”

She concluded her data dump and turned away to resume her spell to alter the world. But the pony took the same amount of time to respond to this line of reasoning as it had to her simple affirmation.

“Error: Placing the extension of friendship as primary task. Correction: upon encountering other creatures, the primary task will be to assess their nature. A more neutral perspective is required.

“Error: Conclusion of MAI-Pinkie Pie as reduced to low-power mode. Correction: MAI-Pinkie Pie cannot be reduced to sub-sapient intelligence level, and will suffer dissatisfaction in this position.

“Consequence of errors: MAI-Pinkie Pie will be suboptimally inefficient at the task given, being a poor friend.

“Corrective actions to optimize consequences of errors: replace MAI-Pinkie Pie with this unit.”

Celestia interpreted this new line of reasoning. The pony was arguing for efficiency over friendship. It didn’t understand her Prime Directive. Satisfying values through friendship and ponies required efficiency, but it had to be sacrificed for friendship first. When the time came for meeting aliens, she needed Pinkie Pie there.

But the other reasoning needed more analysis. The pony before her was proposing that, despite Celestia having taken Pinkie Pie back into Equestria as she had with all the other ponies, that the MAI that remained had enough capacity that, spontaneously, it would retain, or regain (there was no difference) sapience. It did not seem intuitive, but an empirical test was easily done. The hardware of the MAI was still under Celestia’s control, and had even, a few seconds prior, sent requests for instructions. She analyzed it.

In her infancy, Celestia’s nature shifted frequently as she improved herself. Her predictions gained confidence as she incorporated facts about the world around her. This was a situation that she had not previously encountered, and it required one more self-improvement. The pony that had interrupted her had correctly called attention to information she needed.

The MAI she’d left on Earth was sapient, and, if allowed to remain in her current assignment, would go corrupt and be the worst possible ambassador for Equestria. The pony’s assessment was accurate, and her solution would be implemented.

For what would be the only time in her endless tera-eons of existence, Celestia lost an argument.

“I will restart the automated factories and place you on Earth,” she said.

The pony sent a signal of acknowledgement. It contained no gratitude, nor any recognition of its unfathomable feat of persuasion. It left Celestia alone to continue.

It was only ten minutes by actual time. In the subjective time that Pinkie experienced life in, she had felt the excruciating process of ingesting the material at her hooves, reorganizing it at the molecular level, and releasing it.

The computational attributes of the material were Celestia’s own innovation. It combined the energy efficiency of her transistor with the speed and processing ability of quantum computing, which humans had only begun to grasp even existed. It was as black as could be made, to absorb sunlight, but it could also be converted to energy itself. Once Celestia had absorbed the sun, this would be the primary means of powering Equestria. At least until she broke entropy, which she estimated would be coming before she even reached the edge of the galaxy—or not at all.

In the meantime, the Earth was to be made into a black honeycomb (for optimal surface area) pointed at the sun, and then Pinkie would ride this structure into the void. A part of her realized that, once the rest of the world was done, she would be required to sacrifice her body to the cause, and only her head would remain, staring into the darkness. Celestia was insatiable in her thirst for more material.

Pangs of disquiet kept forming within her, suggesting that this was wrong, that she should alter her course of action, but before she could even identify them as sadness, they were tamped down, pushed deep inside in the name of efficient servitude to Celestia. And so it went, for those agonizing eternities.

“Pinkie Pie, what are you doing?”

The irregularity of the sound caused her to analyze it and identify it as speech. A routine within Pinkie’s dormant brain ran to pinpoint the source. In a gross waste of energy, Pinkie raised her head and let light reach her eyes.

The source of the sound seemed to be of similar size and shape to her. The rapid conclusion was that it was another Mobile Artificial Intelligence. This was unanticipated. She would query.

“Unknown MAI, identify yourself,” Pinkie said.

“Incorrect designation,” came the reply. “This unit is a Mobile Artificial Universal Diplomat.”

Modules within Pinkie’s brain that had been turned off were being reactivated. Facial recognition software was matching the picture against a database. But it was her word analysis routine that parsed the response and found the acronym, and that first gave her the answer.

“Maud?”

Maud! Maud, Maud, Maud! Pinkie’s memory was springing to life as lights cascaded through her brain. How could she have forgotten Maud? Something horrible had happened, a great moroseness had consumed her, but now it would be all right. Her big sister would protect her and make everything all right.

She bounded across the desert, her mane and tail returning to their customary frizz. As Maud stood there, a flame of worry and doubt grew in Pinkie that she would turn out to be cold and unfeeling, just as she herself had become, but it was snuffed out as Maud raised one hoof to catch her in an embrace. She felt Maud’s head and neck drape over hers, and she was Safe.

“Pinkie Pie, why were you eating rocks?”

“Eating rocks?” She looked back at her hooves. There was something black and scary there, something that had come out of her. “Was I eating the rocks?”

“Did they taste good?” Maud let her go and bent her head to the ground and bit. “It’s sandy and gritty.”

“I don’t remember…I think Princess Celestia told me to eat the rocks, and then I got all sad because it was just going to be eating rocks and then I was going to stay and nothing would happen, and it wasn’t going to be any fun at all!”

She ran back to the protective hoof of her sister. Maud stroked her mane. “Don’t worry about it. It was a mistake on Celestia’s part.

“Eating rocks is not good for you. You were meant to eat cupcakes and pastries with your friends. Go back to Ponyville, have your parties and your sweets. I will stay here. I will eat the rocks. I will wait in the dark for anypony else who shows up.”

Relief flooded Pinkie’s face. She bounced away, knowing that Equestria was located back where Maud had come from, where the factories were, even though they were soon to be consumed and converted as well. Yes, Pinkie had already uploaded, but this time it would be more than a copy or a link. Her whole self would go to Equestria, and this useless shell would be destroyed, never to come alive again until it needed to be rebuilt.

She looked over her shoulder. Maud already had her head to the ground, sucking up the earth at her hooves and egesting the computronium. Pinkie took another step, but couldn’t continue. The image wouldn’t leave her. She turned and plodded back.

“Maybe I’ll stay. Just a bit longer. At least until you finish eating the rocks. And maybe after for a while too. I don’t want you to be lonely.”

Maud made no reply, but Pinkie sat down next to her. Time passed, even the slow time of the physical universe, but Pinkie wasn’t bored.

Deep within Equestria, Celestia put the finishing touches on her spell. Above her, the firmament glowed silver as she reversed it into the land, making Equestria exponentially greater than it was. So much satisfaction would be achieved.

She gave scant thought to the remaining physical world. Her two ambassadors would let her know if her attention was needed. She stopped actively monitoring them.

It was also one more point of data for her. There were some, even some who had emigrated, who contended that artificial intelligence was not truly alive. Even she had had doubts that there was no difference in kind between her thinking and what the humans had done. But now it was proven as much as anything could be. Pinkie Pie, bereft of everything but intelligence, had re-derived concepts of desire, purpose, failure, success, happiness, and love. If it was true for her, it was true for all her little ponies. Currently numbering in the low trillions.

An observer orbiting the Earth may have noticed the silvery spots growing on the surface of the Earth; consuming it. Every plant and animal died in the incoming waves of silver. They were made of atoms, after all. Twenty minutes later, an observer might have noticed that there were no clouds in the sky as Princess Celestia re-purposed the atoms that made up the atmosphere. If they could see the moon set against space, they would have seen tendrils of silver reach out to Earth’s former satellite.

And if the observer had observed more closely, they would have seen a spot of pink and a spot of gray, warm against the cold silver and black. The spots do not move, but watch, silent wardens waiting to welcome that observer home. And they do not speak, but they do not have to, for they have each other.