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I have this fan theory that Opaline from My Little Pony G5 was a former student of Princess Twilight Sparkle similar to how Sunset Shimmer was Princess Celestia’s former student. I think that Opaline was Twilight’s student who was just a unicorn with special magic abilities before she turned evil because she wanted to be the most powerful pony in all of Equestria and that she wanted to conquer it to gain ultimate power and control over everyone around her. I also think that she took part in dividing the peace and unity between all ponies and creatures (except not all of them according to my Alternate Universe of My Little Pony also known as MLP: Age of Equestria). I also think that Twilight Sparkle made the mistake in turning Opaline into an Alicorn or that maybe Opaline herself found a spell that transformed her into an Alicorn and that she became an Alicorn Queen once she had divided the ponies and creatures from each other. Who knows? Maybe in the future, we might know more about Opaline and if we do get a backstory on how she became an Alicorn and if Opaline being Twilight’s former apprentice was canon, then I would love to see that. What do you guys think of this fan theory? Comment below and share your thoughts.
 
My Little Pony, Twilight Sparkle, Opaline (c) Hasbro  
Artwork (c) MelSpyRose