A third storyline might be centered around Twilight Sparkle's little brother facing a challenge that only he can solve. He discovers a strange magical phenomenon in the outskirts of Ponyville. No one else seems to understand it, but with his fresh perspective and determination, he manages to figure out how to stop it from causing harm to the town.
Another storyline could be about Twilight Sparkle's little brother making friends in Ponyville. He could meet all kinds of ponies and have unique adventures with them. Maybe he forms a special bond with a group of young ponies who are into different kinds of art, like painting and music, and they all learn from each other.
One interesting storyline could be Twilight Sparkle's little brother getting involved in her magic studies. He might accidentally cause some chaos in her study area with his own budding magical abilities. For example, he could make all the spell books float around in a disorganized mess while trying to help Twilight organize them.
Celestia and Luna might also show up in some fanfictions. Celestia could offer wisdom to Twilight Sparkle's little brother, or Luna might appear in his dreams to give him hints about a mystery he's trying to solve. Their presence would add an element of grandeur and magic to the story, connecting the little brother's small - scale adventures to the larger world of Equestria.
One idea could be that the twin brother has a different magical specialty. For example, while Twilight Sparkle is great at magic related to friendship and harmony, her brother could be more attuned to magic of the elements in a different way, like having the power to manipulate natural elements more directly. Maybe he could use his magic to help protect Ponyville from a new, different kind of threat that Twilight's magic isn't as effective against.
First, you can start with his appearance. He could look similar to Twilight but have some distinct features, like a different color in his mane or tail. In terms of personality, he might be more outgoing than Twilight. For example, he could be the type to easily make friends with everypony he meets. This would contrast with Twilight who can be a bit more reserved in new social situations.
One interesting aspect could be the different interpretations of Twilight Sparkle's character. In fanfiction, she might be placed in various new situations, like exploring a new magical realm that wasn't shown in the original series. This allows fans to see how she would react and grow in these unique circumstances.
In some fanfictions, she could die sacrificing herself for her friends. Twilight is extremely loyal to her friends in Ponyville. So, if there was a situation where her friends' lives were in danger, like from a powerful villain, she might choose to give up her own life to protect them. This would be a very heroic and in - character way for her to die.
One interesting 'twilight sparkle filly fanfiction' could be about her first attempts at magic as a filly. Maybe she accidentally turns her room into a mess of floating books and strange potions.
One interesting story could be about Twilight Sparkle using her gaming skills to solve magical mysteries in the virtual world. Maybe she teams up with her friends and they encounter various challenges that only her unique gamer knowledge can help overcome.
Well, often in 'insane twilight sparkle fanfiction', the plot twists can be really engaging. The author might take the concept of Twilight's intelligence and turn it into something that causes chaos. Maybe she discovers a new type of magic that drives her a bit mad and the story follows how she and her friends deal with this new Twilight. It can be a really fresh take on the My Little Pony universe.
One interesting story could be about Twilight Sparkle discovering a hidden dragon lair and having to use her magic to communicate with the dragons there. It might involve her learning about dragon culture and forging new friendships.
One interesting plotline could be Twilight Sparkle struggling to adapt to the changeling society while still holding onto her own values. For example, she might have to learn their ways of communication which are different from ponies.