Funny thing about chaos theory, even the smallest change can have consequences...
"The Elements!"
This is called the Butterfly Effect...
"TWILIGHT!!!"
I admit something might've changed, maybe I wasn't supposed to be here, I don't know, I'm just monologueing here.
"Oh, Twilight, thank Celestia you're alright!"
Or maybe it's the nature of Paradox Space itself, things change to accommodate me, after all...
Paradox Space has a strange sense of humor.
"She went up there!"
All the six ponies could do, after spending a while trying to find their way around the old abandoned castle, is stare from the doorway. The sight? Nightmare moon on the floor, in tears, with a suspiciously familiar charcoal black stallion at her side, comforting her. No, you heard me right, a mysterious stranger had put a malevolent spirit to tears, and started comforting her. Even Pinkamena Diane Pie herself is dumbstruck.
"I don't blame you, 1000 years would've done this to anypony."
"That doesn't matter, I'm a horrible pony!"
After about an hour, the Mane Six are still staring, Celestia was released, after which she started staring while Nightmare Moon apologized profusely, then, in an anti-climatic finish...
"I don't even deserve to exist!" Nightmare Moon then throws off her armor quickly, and absconds quickly in gas form into said armor, leaving a blue filly behind.
Instead of asking questions, the seven ponies look towards a smiling Cosmic, who is occupied by trying to wake up the sleeping filly, he looks up. "What?"
Twilight is the first to speak up, "How did you... what did you... I mean......... what?"
"Wasn't it obvious? I thought that's what the whole rush was about."
...
"Were you looking for the Elements... to banish her?"
...
"Don't worry, ponies have a long history of misunderstandings... which I'm sure this is."
Celestia pulls herself together, "I think my little ponies are just confused as to how you figured out she... could change, at least through words alone."
"I already knew, I just pointed out a couple things and she just broke down."
"But what did y'all say?!"
"Um, maybe we should talk about this later, my sixth sense tells me there is something else important to cover."
"That's right, Twilight, did you find any similarities between your new friends and the Elements?"
"Uhhh... OH! Of course! They represent the seven Elements of Harmony!"
Ugh... That was an odd shiver... Cosmic thought, probably just my destiny sense acting up again.
"Applejack, who reassured me when I was in doubt, represents the spirit of... Honesty."
"Fluttershy, who tamed the manticore with her compassion, represents the spirit of... Kindness."
"Pinkie Pie, who banished fear by giggling in the face of danger, represents the spirit of... Laughter."
"Rarity, who calmed a sorrowful serpent with a meaningful gift, represents the spirit of... Generosity."
"Rainbow Dash, who could not abandon her friends for her own hearts desire, represents the spirit of... Loyalty."
"And Cosmic Enigma," There's that shiver again, "who thought about Nightmare Moon when nopony else cared, represents the spirit of... Understanding."
Celestia used her magic to break apart the rock-like Elements to let out crystals, which circled around their respective spirits in their strange glow.
"And when these Elements are ignited by the spark of friendship, it creates the Seventh Element, the Element of Magic!"
Although Cosmic wasn't put through the trials the others were put through, he did have a good long nap behind Nightmare's throne after looking for the old library to scavenge old books from. The others still felt the same sort of bond with him, Twilight, from their talk in the archives, and the others from his Pinkie 'Welcome to Ponyville' party.
Despite this, he was still on most of their minds, particularly during Pinkie's next party, like Luna while she trying to take her mind off of how quickly everpony had accepted her.
"Sister, who was that stallion?"
"I honestly don't know. When I was sure the other Elements were taken cared of while planning on sending Twilight to Ponyville, I got an odd letter. It told me to not worry about Understanding and that everything would fall into place as expected. It had an image of a sun on it."
"Like your Cutie Mark?"
"No, it looked different somehow, but I still felt as if I had seen it somewhere before, and whoever wrote it had a colorful vernacular, and uses metaphors way too much.
In the end, the seven friends were sure going to have lots of adventures together, but we don't care about that, we care about what happens outside of saving the world... wait... what do you mean you care? Too bad! This is about their ordinary non-catastrophic issues of everyday life!
Ugh, fine, you can have a couple of friendship reports thrown in.