He had been working on a personal project when she had abducted him. "It'll be fun! Come on, do something different." He couldn't refuse her anything. They both knew that. But that was a low blow.
He was not sure what they were celebrating, assuming that's what they were doing, or the significance of the date, or any of the other elements that brought this decision about. He could think of several possibilities, naturally, although none of them seemed likely. If he had to decide upon a catalyst, he would assume it was just her being herself.
He could understand the appeal. She had forever, and saw and knew everything. It was hard enough for him, and he had the merest fraction of what she did. To remain stable, you had to occasionally allow a sudden and extreme change. Abandoning her purpose and responsibilities for an irrelevant period was simply giving her the opportunity to do so.
Regardless of possible motives, she had taken him here, to this strange dimension, and made it plain the two of them would be here for an arbitrary period of time. So for a month, as the inhabitants measured things, nobody in any of the universes would be born or die, while the two of them existed... here.
Thanos began analyzing the interior with his extra senses, and quickly found the dimension to be a strange place. It was a tiny world, so small that when he utilized his advanced optics he could actually see the back of his head. No more then some dozen hundred kilometers in width then. And, in a valley near some rather severe topography, there was a village, inhabited by a race of quadpedal mammals in a variety of strange hues, who lived in a utopia, or at least a primitive approximation of one.
He places them at around zero point zero four on the great filter, and zero point zero point two on the Kardashev scale. If he was generous. Their society was inefficient and wasteful, with most of the production geared to purely irrelevant constructs, however given that any conceivable material want was within reach (at least, from their very, very limited perspective) he assumed that the roles only actually existed for the purpose of personal direction. He himself had little interest in society, or even spending time with other beings. But even as societies went, this one was lacking. They passed around valueless commodities but attached no value to any of them, giving them no purpose in the transference in the first place. It was all completely arbitrary.
Though it made sense, he supposed, inasmuch as any of their strange society did. He remained confused as to how they built the structures they lived in, given that they had no evidence of harvesting the raw materials for the purpose of construction, and lacked the ability to shape them given their forms and capabilities. All in all, when attempted to analyze them, he met several discrepancies that suggested he had only a fraction of what he needed to really comprehend anything he saw.
He was more confused as to the physics of the place, or lack thereof. It lacked the density and mass to produce a sufficient gravitational field, the atmosphere should be too thin to properly create the required patterns to even have wind, let alone allow them to breathe, and keep the suns rays from burning the planet to create a lifeless rock. At last he'd identified to minor godlings in the heavens, and realized that it was all simply a product of them, and he'd promptly lost interest. For a while, he'd thought of going up there and challenging them, but given the society they'd built he doubted that would actually serve as something to challenge him. And if one did not challenge and seek to surpass oneself, what was the point in anything?
She was having fun, of course, not bothering about any of this. The second she arrived, she transformed into a black and white pony with an Ankh birthmark and began frolicking with the rest, swallowing herself up in their games. He was a bit jealous at their attention, but managed to repress it and refocus. Given he had, as it were, nothing to do, he tried to find a problem to unravel. None of the ones he identified served to do more then irritate him at their inconsistencies. So he spent the first day focussing on the tiny pocket universe, deconstructing and reconstructing it until he was familiar with every inch at a sub-atomic level, understanding everything from the movement of tachyons to the various broken systems that made the world inhabitable for those not as advanced as he.
The next day, he began shifting elements to be more to his liking, without unduly effecting the inhabitants of this world. He didn't much care for them, but she did, and if he ruined their lives she'd be hurt. So reforming it all was hard, as there was precious little ambient energy he was able to manipulate to his will. Their sun was so small it should have burned out in exactly one rotation, and that was the least of it.
"Are you doing magic?" The creature that asked was diminutive, especially by his standards, and soft. If he did not expend significant effort when he touched it, it would break, crushed beyond recognition. It's skin was a shade very different to every other he'd seen so far, and more to the point it had a small nub of bone poking through it's hair at it's forehead. Based on the pheromones it was emitting it was female, based on the age of it's cells it was young and apparently it was too curious for it's own good.
They'd observed him before, but had the sense to let well enough alone, avoiding him for the most part, the way he preferred it. Apparently this one had no sense of self-preservation, or instead was too curious for what it had to make a difference. If natural selection existed on the planet, he would be doing ponies to come a favor by eliminating this one. But given they lived lives free of adversity, he supposed there was really no point. Eventually, some dimensional conqueror would come and then where would they be?
So he didn't respond. He had better things to do then waste time with a being who could not even begin process ten of the verb tenses to explain what he was doing, let alone how he was doing it.
"What are you doing then?"
He narrowed his eyes, then shrugged. "Attempting to reconfigure reality by influencing all matter present on the lowest possible level, to an extent that I can reform aspects of your world. I will then begin restructuring elements, causing alteration at it's most fundamental level. When I succeed, elements should become clearer as to why."
"..." Twilight Sparkle had no idea how to answer that. Thanos resumed his concentration. Realizing she would have to be more proactive to get this big thing to open up, Twilight Sparkle neighs softly. "Why what?" She asks at last.
"Why is the only question that matters. Why this exists. And that will lead me to how this exists, and so I should, if the whim ever took me, be able to recreate it." He replied, one tenth of his mental processing power that should be measuring the energy output of the sun and calculating how it seemed self-sufficient distracted from it's task by her and her questions, superlative mental concentration nonwithstanding. That was irritating.
"That seems silly."
"Does it." It's not a question, it's a closed statement, hoping it would close the conversation. He really had no interest in talking to her. Then again, he was not as a whole equipped for a conversation with another being.
"Well, yeah. There are so many more interesting things to dedicate time to. Like friends."
He pauses. His universal communicator was having trouble with that last word. He didn't actually understand her, so much as he read her mind and filtered it through several inhibitors to allow him to understand what she meant. It takes him a moment, then he shudders slightly. "What a terrible concept." He says, with genuine shock.
The pony laughs, not at all understanding how the idea of friends would sound to a failed attempt to create a supreme intelligence, that was driven by extreme nihlism to the point of being unable to see the value of anything that was not written in to the very fabric of reality. "I didn't have any friends at first, either. That's why Princess Celestia sent me here. Did she send you here as well?"
"No."
Dear Princess Celestia, Twilight Sparkle.
Today I learned that some people like different things to you, and sometimes the best intentions get taken the wrong way. But just because you don't understand something you shouldn't be scared of it.
Your faithful student,