Celestia's ambassador came in and bowed.
"Your highness," he spoke. "I've just returned from the foreign land called the Mushroom Kingdom. The princess would like to speak to you and discuss an alliance."
Celestia nodded and smiled.
"Gather the chariot team. We're going to the Mushroom Kingdom."

Princess Celestia travels to the Mushroom Kingdom - a country strange enough to have been made by Discord. There, a certain surprise is waiting for her. Some would say, it's just another day in the life of a princess.