One idea could be that Spiderman gets transported to Equestria where he meets Twilight Sparkle. They could team up to stop a new villain that is causing chaos in both the human world and Equestria, perhaps a villain who has the power to open portals between the two worlds and is using it to steal valuable things from both. Twilight could use her magic to help Spiderman understand the new world he's in, and Spiderman could use his combat skills to protect Twilight when they are in dangerous situations.
Maybe it begins in Equestria. Twilight Sparkle is doing some research in the library when she discovers a strange spell. When she casts it, a portal opens and Spiderman comes tumbling through. He's disoriented but quickly realizes he's in a very different place, and Twilight is equally surprised to see this strange human - like creature with such unique abilities.
A likely candidate could be Discord. He is known for causing chaos and mischief. He might pretend to befriend Twilight Sparkle only to betray her at a crucial moment. Another possibility is Trixie. Trixie has been jealous of Twilight in the past and could betray her out of envy.
One possible plot could be that Spider - Man gets transported to Equestria. Twilight Sparkle discovers him and is initially cautious but then realizes he has good intentions. They team up to fight a new threat that is causing chaos in Equestria, perhaps a villain who has the power to manipulate magic and technology in a dangerous way.
A combination of Green Goblin and a chaos - causing creature from Equestria. The Green Goblin could team up with this creature and use his glider and bombs along with the creature's ability to spread chaos. They would target both Spider - Man's city and Twilight Sparkle's home, causing destruction and trying to assert their control.
Flash Sentry could be a likely groom. He has shown an interest in Twilight in the past and they have had some interactions that could lead to a romantic relationship. Another option could be a completely new character, perhaps a powerful wizard or a prince from a far - off land who Twilight meets during one of her adventures and falls in love with.
The main difference is the 'insane' factor. Regular fanfiction might focus on Twilight's normal day - to - day adventures, like studying magic or helping her friends with normal problems. But 'insane twilight sparkle fanfiction' will likely take her into more extreme situations, like having a mental breakdown due to magical overload or some other crazy event.
Fanfiction about Twilight Sparkle being banished can also be a vehicle for exploring different relationships. Maybe she meets characters she would never have interacted with in the show. Her banishment could bring out different sides of her personality. She might become more resourceful or develop a stronger sense of self - reliance as she tries to navigate her new situation.
One great 'Twilight Sparkle Fanfiction' is 'A Magical Friendship'. It really delves into Twilight's growth in magic while also strengthening her bonds with her friends. The story has a lot of interesting plot twists and the characterizations are on point.
It could be a pony who is extremely extroverted if Twilight is introverted. Someone who loves chaos and spontaneity instead of Twilight's love for order and planning.