A long, long time ago, longer than the memory of any living beings except for a few immortals, two unicorn sisters lived in a village of ponies.
In these days, being a pony was hard and dangerous, because there were countless threats that were powerful enough and willing enough to cause their extinction. Many evil beings, dangerous artefacts and nocive phenomena wandered through the world causing pain and terror to any who had the bad luck to cross their paths. Many powerful, intelligent species ended up disappearing from the world in those days.
Those two unicorn mares knew about it, and ever since their childhood, the two had wished to be able to protect their families, friends and their way of life. As such, they hoped their talents would turn out to be powerful and useful so they could help protect their village.
That was not an uncommon notion, and the numerous small pony gatherings managed to survive long in that harsh world thanks to the many ponies that worked hard to protect them.
It wasn't different with those two. They eventually discovered within themselves the talents of Sun Magic and Moon Magic, respectively, and as tradition, took on new names to reflect her talents, becoming Celestia and Luna.
They learned all they could from their elders, developing their magic and shaping it to become the strong warriors the village needed for its survival, and the two soon proved their determination, as before they were even out of their teenage years, Celestia and Luna had surpassed their teachers and become the greatest mages and warriors in the village.
From them on, they took on the responsibility of their power with an impressive dedication. Always being the first line of defence against threats such as monsters and raiders, as well as frequently scouting around for bigger threats that they would need to relocate their village to avoid, thing that happened three times during their years as guardians.
The job of protecting their village pushed them to their limits and almost broke them several times, but they grew stronger due to it, and kept on living their lives day by day, because what else could they do in such uncertain times?
But one day, they were faced with something completely out of their experience:
A Battle of Titans.
Discord was the Spirit of Chaos.
But despite, rightly, being considered a dangerous villain by pretty much every single civilization which had ever met him, Discord was actually far from being the existence which caused the greatest harm in the world.
After all, things wouldn't be any fun if he was alone in the world, or if the world itself was destroyed. And as such, he actually used a lot of restraint in his dealings with other beings, relatively to some of the greatest evils, of course.
Case in point was the entity he was currently facing.
Once it had a name, but it had forsaken all identity in a mad quest for power and was only known as the Nameless Abyss of Darkness. Once it had been a part of some species, but was now only a living (if you could call that life) maelstrom of darkness.
And it wanted to devour the entire world, covering all existence with its darkness.
Discord obviously opposed that. After all, the world was his toy and he wouldn't simply let any random monster destroy it when it wanted.
And so they fought.
And despite his colossal power, the Spirit of Chaos actually found himself matched by Nameless.
Discord clapped to make pieces of his opponent be scattered all over the world, but in every dark spot Nameless regrew and joined together, Discord summoned an infinite army of wind up toys to eat every single portion of the maelstrom, but they were all eaten from the inside, Discord banished the Abyss to a world of pure light, but the Darkness devoured all the light leaving only more darkness behind, and broke out of the world by chasing the darkness in Discord himself.
And Nameless wasn't only defending, it kept trying to consume Discord and every single spell he used, desiring to smother such a powerful being that would leave a lasting darkness behind. It started to take in more and more darkness from all over the world, growing bigger and bigger, with the goal of filling every empty space in existence and leaving Discord nowhere to escape.
Seeing that he had no other guaranteed way of defeating the opponent quickly, the Spirit of Chaos decided to do something he didn't really like.
"CHAOTIC RELEASE!" He shouted.
And even though Nameless was powerful, he was completely one upped by Discord at that moment, as the Spirit of Chaos removed all of his restraints.
Every single being and every single piece of matter in the world, became Discord.
"Ha, Ha, Ha!" Discord laughed from his uncountable mouths.
And every single Discord attacked the Abyss at the same time, with countlessly varied attacks that hit the enemy all at the same time, in total defiance of the laws of space and time.
But even in the face of such overwhelming assault, Nameless remained in existence, his soul anchoring itself to the wound in reality his existence was, thus remaining in the world despite every single bit of darkness having been annihilated.
But Discord wouldn't be stopped by such a method. He laughed again and used a colossal amount of power to briefly take control of the essence of the world, which he decided to channel through the sun and the moon who were in the sky.
Accelerating both to relativistic speeds, he made them crash directly at the wound in the world, forcefully healing it and leaving the damaged soul of Nameless to disperse.
But even Discord couldn't use such a large power without consequences. His body started cracking apart, and he instinctively disabled his Chaotic Release, returning to a more stable state and falling to the ground, his energy spent.
However, he then looked up and realized something terrible. Perhaps due to a last curse by Nameless, perhaps due to his own excessive power lacking control in his unrestrained form, or perhaps due to a combination of both factors, the sun and the moon hadn't returned to their usual orbits after he released them. In fact, they seemed to be speeding up... and falling.
Realizing that such a catastrophe would destroy the world, Discord attempted to get them back under control, but his power failed him, being too exhausted to exert enough power to stop something like this.
He watched in despair, deciding to never again use his unrestrained state, because it had made his own worst fears come to pass.
Celestia and Luna were the first to wake up from the groggy state after turning back into themselves from being Discord. This was not due to any particular strength of theirs, but because of their connection with the sun and the moon.
While most other beings in existence were still trying to remember how to open their eyes and stand up, the two unicorn sisters had seen the out of control celestial bodies rushing through the sky and slowly descending. And they understood exactly what would happen if they crashed into the land.
So Celestia and Luna reacted the same way as they would react to any other threats to their home, and tried to solve it, first by using magic on the Sun and Moon.
The feedback of trying to use their meager powers to stop the out of control celestial bodies gave them a terrible headache and almost knocked them out, and the two saw that this wasn't going to work.
And them, almost at the same time, they had a crazy idea. Perhaps instead of trying to use their own powers to stop the sun and moon, they could connect with them and make it so they would stop themselves.
Using only intuition, they wove new spells to connect themselves directly with their celestial bodies, and were instantly flooded with power.
It was beyond painful, and both of them screamed as they tried to control the power beyond anything they had ever experienced.
Their bodies started to be burned away by the sheer amount of energy passing through them, but the two refused to stop their spells, knowing this was a battle for the fate of their village, and only having some idea of what it meant for the world, as their minds couldn't concentrate on much.
Discord felt the two ponies trying to save the world and undo his mistake. He wished he could help them, but he was unable to, and he understood very well that their efforts would simply not be enough.
Still, their determination to not give up even as their weak bodies were destroyed by the power they were trying to wield moved him, and he decided that he should do something to honor it.
He couldn't help the two, but he could make it so he wasn't the only one who knew of their desperate battle. And with a spell that took all of his remaining power, he tried to connect their minds with that of every single other intelligent creature.
His power wasn't enough for what he had in mind, but he managed to connect them to every pony in the world, and he decided that was enough as he passed out.
And at that moment, every single one of the thousands of ponies could feel the plight of the sisters, and their determination, and not knowing what else to do, they started cheering the two on, even if most of them didn't even know their names before the ponies of their village, which were also in the connection, revealed them.
And the sisters felt every single pony in the world cheering them on, and realized the immensity of their task for the very first time.
Finally, their bodies couldn't handle any more of the power and exploded.
But for a moment, before they could drift away, their souls were free of the confines of flesh, and in a final effort, used every single scrap of will they could muster to move the energy and force the sun and moon to stop.
And then Celestia and Luna's souls exploded with light, as new bodies constructed themselves around their souls, bodies that were utterly different from what they had before, and yet, completely right.
That was much cheering on that day, even after the spell broke and the connection of the ponies vanished. Celestia and Luna hugged each other in content, but then they started to discuss things.
They had felt how many ponies that were in the entire world, and they now felt responsible for them.
Perhaps it was fate that the two had become so much more powerful just after that, as they decided they had to protect all ponies, instead of just the ones in their village.
They would gather every pony in the world under their protection, and as they had done before, Celestia and Luna would act as protectors against every threat.