Twilight had been invited to Canterlot by Princess Celestia, no emergency, no important task, just a friendly get-together between mentor and ex-student. She didn't often get time to spend with her former teacher to just bond. Usually they were both busy with Princess-ly duties and only saw each other during disasters or celebrations.
Twilight had gotten the letter via dragon-breath two months in advance, Celestia knew how far ahead Twilight liked to plan things down to the exact minute. Between her teaching and overseeing of the School, obligations as a Princess, and missions as the Element of Magic, she was lucky to find time available for the occasion. She left Spike in charge of her castle and left for the afternoon, soaring over Ponyville towards Canterlot.
The Princess of Friendship was formally welcomed by a Guard upon arrival, and escorted into the Royal Castle. She was led into a well-furnished room where Celestia was already waiting, a small assortment of teas and cakes at the ready. Twilight greeted and hugged her past mentor, then they sat down and started chatting away.
They talked about many things, how the School of Friendship was going, their diplomatic relationships with the other nations, recent Friendship missions, and reminisced on many of Twilight's previous accomplishments.
"Do you remember the first Summer Sun Celebration you spent in Ponyville?"
"How could I? You assigned me to plan the whole thing! And then everything went to Tartarus of course, but I met all of my best friends too!"
"Indeed, you don't know how happy I was when you united the Elements and brought my sister back. I had spent a thousand years planning for that night."
"So you did know that Nightmare Moon would return that day! I didn't think much of it then, but you sent me to Ponyville on purpose to find other bearers for the Elements!", Twilight took a sip of her tea just as a thought popped into her head.
"Princess, if you had a thousand years to prepare for Luna's release, why didn't you find bearers for the Elements during that time? Or even just used all of the Elements yourself like you did when you sealed her in the moon?"
Twilight could tell they were hitting a more serious topic, as Celestia actually put down her cake.
"Using each of the Elements of Harmony at once is an enormous magical strain on the body, not to mention properly bonding with each of them. I doubt anypony other than an alicorn would be able to handle two, let alone all six. Splitting the burden between six ponies makes it much easier, just like the Pillars did, who created the Elements in the first place. That's why before, Luna and I each wielded three, and why I desired to find another group of six friends to take my place. After two or three uses of all six I doubted I would be able to do it again unscathed. As for what I did during that millennium, I was looking for more bearers, and I did none too soon, as you found them the same day my sister returned."
"So, ever since I was accepted into your School for Gifted Unicorns, you were preparing me to lead the Elements of Harmony with a group of friends?"
"You're quite right, in fact, that's why I opened the School in the first place, to find a talented young unicorn who could live up to Starswirl's legacy. I was worried at first upon seeing your interactions with Moon Dancer, Lyra, Twinkleshine, Lemon Drop, and Minuette. But you made some new friends in Ponyville and bonded with the Elements just in time to stop Nightmare Moon!", Celestia smiled.
Twilight blushed remembering her old group of friends in Canterlot and how she used to be, more concerned with studies than socializing, and then coming back to see how Moon Dancer had become the same way. I really should visit them more often, especially since we started making up for all that time apart.
"Is ... that the same way you felt about Sunset Shimmer? Before, you know ...", Twilight said, bringing up her mentor's previous student. Celestia looked down at the floor briefly, almost kind of, sad.
"Much like you, Twilight, I had high hopes for her as well. I recognized both of your natural gifts at a young age and enrolled you in my School. I watched both of you grow and sharpen your magical skills for many years. Sunset was actually my first choice between you two, she had several close friends and was far more outgoing and independent. I told her about the Elements and my hopes for her future first too. Unfortunately, I failed to see a darker side to her personality, her hunger for power and control. When I thwarted her plans, she escaped into another dimension. I had hoped it would be better for her, to find herself and develop humility in a different environment. But then she returned and stole the Element of Magic, your crown, with the intent to create an army of demons and rule over others."
Celestia stopped for a second and looked back at Twilight, who was stuck wide-eyed.
She chuckled, "Let's end that on a happier note, shall we? I heard that with the assistance of your friend's doppelgangers, you managed to defeat her and helped her to change her ways, and now the two of you are pen pals?"
Twilight perked up, "Oh, yes! We write back and forth from time to time and shes actually defeated evil there several times, including the Sirens that Starswirl sealed there and a Nightmare version of myself!"
Celestia raised an eyebrow. Interesting, is there an alternate version of me there as well? I'll have to ask her some other time.
Twilight ate some more cake before continuing, "If you don't mind me asking, how many personal students have you had if you've been looking for a new Element of Magic for a thousand years?"
"Probably not as many as you'd think, Twilight. Somepony with your level of magic and skill doesn't come around often. And even then, some would choose a different path, some would give up early, and some would try their hardest to no avail. You are the first to succeed with bonding to the Element of Magic and uniting the other five with a group of close friends. Only two have ever come close, including your sister-in-law."
Twilight almost spat out her drink. "You taught Princess Cadence too?"
Celestia nodded, "Mi Amore Cadenza became an alicorn at a young age from her understanding of Love like you did Friendship. She was adopted into the royal family here in Canterlot, where I taught her much of what she knows. But, once she moved away from Canterlot, she spent most of her time trying to lift Sombra's curse from the Crystal Empire and finding the Crystal Heart."
Twilight was fascinated, I'm learning so much! I'll have to ask Cadence about her time with Celestia when I go visit them again!
"You said 'two', so who else besides Cadence?"
Celestia looked somber again, and Twilight almost wished she hadn't asked.
"If it's too personal of a question, you can ignore it, I-"
"No, you should know their story, Twilight. It might serve as a warning and give you more meaning for the position you hold today as a Princess and as the Element of Magic." Celestia said sternly before taking a deep breath, "For starters, his name was Percival."
