You want to do what?
Twilight Sparkle bowed low before the two regal alicorns that stood before her in their full royal regailia. "Your Majesties, I came as quickly as I could. I'm sorry for the delay; I was in Ponyville. Is something wrong? Has Discord somehow managed to break out of his statue again? Are the Changelings threatening us with further trouble?"
Princess Celestia had a strange smile upon her face. "Nothing is wrong...we called you here because we want you to...to Ascend.To become an alicorn like me and my sister and aunt, who by the way can't be here as she is on her honeymoon in Manehatten with your brother. Rare in the extreme is such an honour awarded to anypony. Think how wonderful it will be to be immortal. Unless you are unlucky enough to be murdered someday or you die in a freak accident, you will be immortal, and you will be able to help me and my sister as we govern Equestria for the good of everypony."
Twilight stared at the two Royal Sisters and her mouth dropped open. "You want to do what? I...I...well, I don't want to seem rude, unpleasent or ungrateful but...but no."
"Are you suicidal, Twilight? Do you want to grow old, wither away and die?"
"No, but I don't want to watch that happening to my brother and my family members and all of my friends and everyone I ever knew. And it's not just that either. If I were to become immortal, I could never show true love to anypony. A lot of ponies would be too scared to date me, fearing I might ruin their career for life or even turn them into a statue in the Canterlot Sculpture Garden if I ever fell out of love with them. Other ponies would be totally overawed, genuflecting repeatedly and saying whatever they thought I wanted to hear. I'm not that kind of pony. Still other ponies would attempt to seduce me so that they could get me to pass laws and regulations that would help them or their companies. And if despite all that I did find my special somepony, then I would stay the same age whilst he or she slowly got older and older and weak and ugly and then died. If I was aging too it would not matter,as we would both be old together. If you want me to agree to become an alicorn...then you would have to let Applejack, Fluttershy, Rarity, Pinkie Pie and Rainbow Dash become alicorns as well."
Both of the Royal Sisters shook their heads and Celestia replied "We are sorry Twilight, but we cannot accept having them as alicorns. If you have too many alicorns in a herd at any one time, it is a recipe for trouble, bickering and perhaps even civil war. Equestria may have been at peace for many centuries, with the exception of the recent Battle of Canterlot, but it was not allways that way. I and my sister have lived in a time when Equestria was involved in total war, and it was anything but pleasent. One of the many things that Discord did to cause chaos for the fun of it was to create more then thirty alicorns. When he was overpowered and locked away in stone, then the alicorns raised their own armies and fought for Equestria until my sister, I and Cadence were the only ones left. One, Sombra, used magic to shut the area he controlled away from the rest of the world. Three others are now living statues like Discord, forever frozen in the Canterlot Sculpture Garden. The rest massacred each other in the constant warfare, apart from my own sister who I banished to the moon for a thousand years. I never want to go back to those war-torn days again. They were truely horrible."
"Nor would I want war to break out again. My Nightmare Moon days are long behind me," Luna said.
"How would you make a new alicorn anyway? Obviously you're not going to let Discord free," Twilight asked.
"We can't tell you unless you agree to become an alicorn." Luna replied. "It is the most classified secret within the whole of Equestria. If it were to become common knowledge then it would be even worse then Discord breaking free, as there would not just be one source of trouble but many. The Alicorn Wars would sooner or later break out again, as almost everypony would try and cheat death by becoming an alicorn."
Twilight sighed. "Your Majesties, I'm sorry, but for the reasons I've talked about I will have to turn you down. One of my friends might take up the offer though."
"Pinkie Pie would be almost as much trouble as Discord if she became an alicorn," Celestia said. "Not deliberately, but just by being Pinkie Pie. Rainbow Dash would very quickly get bored of all the ponies requesting to see her and the administration work within a few days. It's not allways easy being an alicorn. So if you turned the offer down it would have to be Fluttershy, Rarity or Applejack. Fluttershy is not assertive enough and might well end up saying yes to everypony who came to her asking for a favour. The tax bill in the long term would shoot through the roof to pay for it all, and sooner or later would cause resentment and large scale tax evasion."
"Applejack is too honest," said Luna. "That's normally a good thing, but not when it comes to diplomacy. She could end up sparking off a major international incident with the griffins, or maybe even worse. We would not want to end up dealing with a trade embargo. So if it's not you, it would have to be Rarity. Are you sure you want to turn the offer of immortality down?"
"Well...." said Twilight, staring into the eyes of the Royal sisters. "I...."