Was this going to be the end of everything? The end of her homeland? Of everything she knew and loved and cared about?

Twilight Sparkle sat in front of the large monument to Luna and stared up at the tribute to the fallen princess of the night. Her death had come as a shock to everyone, even now the details were kept secret from the rest of the world. Only the royal family knew the truth. Knew of her weakening, how the nightmare from so long ago had threatened to return and overwhelm the princess and how Luna had sacrificed herself to keep it from happening. No pony knew about how the elements had no effect this time, in keeping the darkness from Luna's soul. The public simply believed she had grown ill.

Celestia was once again taking care of both day and night as she had before when Nightmare Moon was imprisoned, but back then she had something to look forward to. She knew Nightmare Moon would be free one day, had prepared to cleanse her sister of darkness. Now, there was no pony to carry the burden but her.

"My student, what troubles you tonight?" The calm voice of Princess Celestia shook Twilight from her thoughts. The young unicorn looked to her teacher, and hung her head. "I was... Just thinking of how difficult all of this must be for you."

Princess Celestia stepped closer and bent her head down to hug her protege. "Twilight Sparkle, this is not for you to concern yourself over. We all miss Luna but she did what she felt was best and I honor her decision. Whatever troubles I face in taking her duties, I do it out of love for her."

Twilight nuzzled against her teacher's neck. "But Princess, don't you wish at all you had some kind of help? Wouldn't it be easier on you?"

Princess Celestia stood and nodded. "Yes my faithful student. It would help greatly, but there is no pony in Equestria who could take this duty from me. I accepted it and I will carry it. Is that clear?"

Twilight sighed and hung her head again, "Yes Your Majesty."

~*~

Twilight was certain that it would be a mistake to leave things as they were. It wasn't that she didn't trust the princess's abilities, she just hated to let her push herself like this. Celestia had confided in her, after Luna returned, that the responsibilities of both day and night were an enormous drain on her power. She knew it was disobeying but she couldn't let the princess put herself through that again. She had come to love the princess like a second mother and after her brother had married Celestia's niece there was no denying that they were family now.

The young apprentice made her way through the archives of the royal library, determination giving her strength to pursue this line of rebellion against Celestia's wishes. Luna was gone, Cadence wasn't ready in either power or leadership ability to assume the role of a leader. There would only be so much Celestia could do to keep the illusion her strength before a neighboring nation decided to test it, even if it took thousands of years, Celestia's power would eventually weaken from too much strain and then...

Twilight pushed away those thoughts. It wasn't what she needed to focus on right now. The royal archives held the collected knowledge of Equestria's most powerful conjurers and magicians. In here she suspected she would find the spell she needed, if it even existed.

"My student." She recalled the words of her mentor, "One of your greatest qualities is how focused you become when you put your mind to something. Your focus is so intense and powerful that when you set out to accomplish something I highly doubt there is any force in the universe that could stand in your way. However, any good strength can also be turned into a weakness. Be careful you don't focus too strongly that you forget what matters most in life."
"I won't Princess." Twilight spoke aloud to herself as she began to pour through the archives knowledge. "But this is something I have to do."

For three days and nights Twilight studied in secret in the archives, learning as much as she could about Alicorns and their magic. Her suspicions were confirmed when a book by Starswirl The Bearded revealed that a pony with strong enough power and resolve could ascend to the level of an Alicorn, but sadly, it would take the assistance of a powerful Alicorn to make the ascension possible. She would need Princess Celestia's help to make her plan a reality.

~*~

The storm quietly rumbled above her as she stood on the roof of the palace, watching the lightning flash in the clouds. She could hear the light hoof falls of the princess behind her. She felt tense as she waited for her mentor to speak.

"Twilight. I know why you called me here." The princess said finally. I already know what you're planning."

Twilight sighed, keeping her eyes on the clouds above. "I'm sorry Princess. I know it was wrong for me to disobey you, but I can't sit by idly when I know I can do something."

Princess Celestia stepped closer, standing beside Twilight and turning her gaze to the storm. "Twilight, this is my responsibility. I know that you are not trying to replace her, just take up her role, but Luna sacrificed everything to keep us safe. She knew she wouldn't be able to hold back her darkness. My student, Luna's throne is tarnished. If I let you ascend to her place as custodian of the night you'll be subject to the same threat of darkness she was..."

Twilight felt the princess's tender hoof on her withers. "Twilight, you are not just my student, you are a dear friend to me. I can't let you put yourself in danger like that."

The young unicorn clenched her eyes shut tight as she tried to summon the strength she needed to voice her opinion. She took a deep breath and pushed away from her mentor. "No!" She cried. "You can't make that choice for me!" She glared at the princess, trying her best to show her determination in her eyes. "Celestia, I've been your student for as long as I can remember. You've taught me everything I know about magic, leadership and independence. You've been preparing me my whole life for something and if this isn't what you've been training me for then you need to either tell me what role you'd have of me or cut me loose!"
She shook with fury, more at herself for snapping at the pony she trusted most in the world than for her indignation. She feared she'd be let go and cast out of the princess's life forever at this moment. She steeled herself for the fury of the sun goddess, they stared at each other for what felt like eternity before Celestia smiled and lowered her head.

"I see. I guess even I cannot stand in the way of your determination my faithful student. Is this what you truly want?"

Twilight nodded. "It is. Equestria was meant to be ruled by two ponies in balance, but I want to do this for your sake just as much"

Celestia approached her and lowered her horn to Twilight's, as their horns touched the young student felt a strong flow of energy pour into her. Her body grew warm and she felt lighter than air. She felt herself lifting into the air as the power of Celestia flowed into her. As it had before on occasion she felt the strong surge of her natural talents breaking free and surrounding her with a powerful aura of magical energy, but now as this power surged from within her she felt Celestia's magic mingling with it, granting her an awareness beyond the aura of her own power.
New senses blossomed within her, as if she was opening her eyes and ears to the world around her for the first time. She experienced everything as like never before. Through the clearing haze of these new sensations she beheld her teacher's true celestial form and heard her speak louder and with more authority than she'd ever heard.

"I, PRINCESS CELESTIA OF EQUESTRIA, HEARBY RECOGNIZE AND NAME THE UNICORN TWILIGHT SPARKLE AS MY EQUAL! FROM THIS MOMENT FORTH I CHARGE HER WITH THE POWERS AND DUTIES AS PRINCESS OF THE NIGHT! MAY HER RULE BE LONG AND PROSPEROUS!"