Years ago, before the days of Nightmare Moon there were three alicorns. Two of them we still know today. One of them has been forgotten. Their names were Celestia, Luna and Stargazer. As you will know Celestia was in charge of the sun and Luna was in charge of the moon. But Stargazer... was in charge of the stars. Every night Stargazer helped Luna with the night. He brought out the stars while Luna brought out the moon. But then Luna changed. She refused to lower the moon. Stargazer was on her side. Hundreds of the ponies who were with Celestia either dissapeared...or died. Then it happened. Celestia used the elements to seal Luna in the moon. Stargazer fled. He hid. While he hid he continued to bring out the stars as usual. But he did it in secret. As not to be found. But then far in the future. After the time Luna returned. That would all change.
------------------------------------------------------------In the future----------------------------------------------------
Celestia paced in the throne room as the stars outside flickered. He was still alive. The very alicorn that had turned against her was still alive. But he was in danger. Nopony knew about him. He had been forgotten by all. All except for Celestia and Luna. Outside the colts and mares looked up at the skies thinking 'what the hell is going on' Celestia was panicking now. If he died everypony would ask questions. Questions that neither Celestia nor Luna could answer. They had to find him. And there were six ponies that could help them.
Twilight and her friends stood in the throne room.
"So let me get this straight." Said Twilight "You have a brother that nopony knows about?" Celestia nodded. The six mares looked at eachother sceptically.
"The only proof I can give you is outside. Look at the stars." Everypony in the throne room looked at the sky. Celestia's eyes widened. The stars were going out. One by one. Like the light of the universe was burning out.
"We have to go." Said Luna "Now."