Equestria was known all across the world for being one of the strongest and most prosperous nations to ever exist. This was due in no small part to the fact that the ponies that controlled the sun and the moon lived in its heart; however, it was more so because its foundation was built on the principle of unity and brotherhood above all else. Through the bonds they shared with one another, the ponies of Equestria could overcome any obstacle that stood in their way. Other nations emulated the practice, but none came close to the love and acceptance that outsiders could feel in the very air itself.
Most of the time, anyway.
It was this strength and unity that enabled Equestria to endure in the great hardship that had recently passed. Two ponies died and almost a dozen were kidnapped in a serial murder case that afflicted Ponyville just over four months prior, and the entire planet had almost been erased from existence by a god much older and more powerful than anything that ponykind could imagine. It was only through the efforts of Princess Twilight Sparkle and her friends that the world had been saved from annihilation, and Equestria had been made all the stronger for it.
Princess Celestia sat on her throne, thinking about what had happened in recent months. She couldn't help but smile at her citizens' ability to resume their normal lives and put such disastrous times behind them. Those events were not forgotten, but no one feared their consequences any longer after such time had passed.
A prodding hoof brought Celestia back to reality. She turned to her right, her eyes immediately meeting Princess Luna's. The younger alicorn looked at Celestia with an expression that was part concern and part sternness. "You've been lost in thought quite a bit recently," she said. "Is all well?"
"Don't worry about me, sister. I couldn't be better," Celestia replied. "There are simply things on my mind regarding the recent murder case and its aftermath. It is nothing important, I assure you."
"Then I beseech you to not let it get in the way of your duties." The concern left Luna's features. "Those...events...were jarring indeed, but they are past us now. Equestria still needs us both."
"And I have no intention on abandoning it." Celestia gestured towards the floor in front of her. "Besides, I don't see anypony requesting my attention at the moment. I'm only using my free time to think these thoughts."
"Actually, there's a guard standing there."
Celestia's eyes widened ever so slightly. She turned to face forward again, and sure enough, a slate grey pegasus in golden armor was waiting patiently with a stoic frown. She held back a chuckle at her own folly. "Is something the matter?"
The guard saluted as Luna rolled her eyes. "Your highness, I bring news from Princess Mi Amore Cadenza."
Celestia's smile grew. "Ah, a letter from Cadence? By all means, let me take a look."
The guard nodded and opened his saddlebag with his wing, then removed a rolled-up scroll with a cyan, heart-shaped seal. Celestia took the letter with her magic, and the guard closed his bag again. Celestia opened the letter and began to read it. Her smile gradually faded as she got further down the page, and by the time she was halfway done, it had disappeared entirely. As she finished, she turned to the guard again. "Thank you for bringing this to my attention. Is there something else?"
"Yes, your Highness." The guard looked slightly uncomfortable. "There is a pony here who desperately wishes to see you. I told her already that day court was over, but she said it was urgent and has refused to leave."
Celestia and Luna exchanged glances briefly before turning back to the guard. "Send her in," Celestia said. "If she thinks it's that important, I should at least hear what she has to say."
"Very good, your Highness." The guard bowed low, then turned around and left the throne room.
Celestia turned to Luna. "Sister, I ask that you write to Twilight in my stead," she said, passing the letter over. "Simply ask her to come to Canterlot as soon as possible, and tell her that I will explain things in more detail when she's here."
Luna stood up and nodded. "It will be done, sister."
Luna flew out the window of the throne room, headed for her personal quarters. Celestia faced the throne room doors again as they slowly opened. The guard entered, along with an unfamiliar mare.
"Princess Celestia," the mare said, bowing. "I take it you already know about the cave..."
