Ulquiorra's development could be slow. Given his complex character from his original source, he might resist the positive influence of the pony world at first. However, as he witnesses the power of friendship, like when the ponies save their world through unity, he might gradually open up and even show a more emotional side that was previously hidden.
In the fanfiction, Ulquiorra could initially view the My Little Pony world as a strange and inferior place. But as he spends more time there, he might start to learn from the ponies. Maybe he would form a special bond with a particular pony, like Fluttershy who is gentle and kind. Through this bond, he could learn about compassion and start to change his cold - hearted ways.
It could be a story where Ulquiorra has to adapt to the pony world. He might encounter ponies who are curious about him and his powers. The contrast between his power and the more gentle magic of the ponies would create an exciting dynamic. He could either become a threat to the harmony in the pony world or gradually learn to appreciate it and even become a part of it in some way.
Some characters might be amused. They could enjoy seeing how the fans see them and their world. For instance, Pinkie Pie would probably find the fun and wacky fanfictions really entertaining.
Their relationship could start off as one of pure enmity. Twilight would see King Sombra as a great threat to Equestria. But as the story progresses, if they were forced to interact more, Twilight might start to see some small glimmers of humanity (or pony - ity) in Sombra. For example, she might notice that he has a love for a certain kind of magic that is not entirely evil.
Their relationship could develop through a series of misunderstandings and reconciliations. Flim might try to trick Applejack into a deal, but she sees through it. However, later on, when Flim is in a real bind, Applejack could offer help. This back - and - forth could lead to a more complex relationship where they learn from each other's strengths and weaknesses.
In some fanfiction, Big Mac's character develops by becoming more talkative. Usually, he's a pony of few words, but in fan stories, he might start expressing his feelings more openly. For example, he could share his thoughts about the family business or his relationships.
First, focus on their appearance. For a changeling OC, you could give them unique markings or a different shape to their body compared to the regular changelings. For example, they might have a horn - like structure on their head that is different from other changelings. Second, think about their personality. They could be really shy because they feel different from the other changelings, or they could be overly confident as a way to hide their insecurities. Third, their backstory is crucial. Maybe they were an outcast in the changeling hive from a young age, which shaped who they are.
You could also develop his character through his relationships. How does he interact with Celestia? Is it a close mother - son relationship, or are there some tensions? And what about his relationships with other ponies? If he's friends with Twilight Sparkle, he could learn a lot from her study of magic. This would shape his character as he tries to find his own place in the world of magic.
Well, in the fanfictions where Rarity investigates, her sense of empathy usually deepens. As she delves into the problems of others during her investigations, she starts to truly understand the pain and joys of the ponies around her. This makes her not only a better investigator but also a better friend. Her creativity also gets a boost. When she's trying to solve a mystery, she often has to think outside the box, and this leads to her coming up with more unique and elaborate fashion designs as well, which is a big part of who she is.
In these stories, Fluttershy often becomes more confident. Taking care of a baby requires her to be assertive and make decisions, which she may not be as used to in her normal life. So she grows in her ability to lead and take charge.
Sora's Keyblade skills would be very useful in the My Little Pony world. He could use it to fight off any physical threats, like monsters or villains. For instance, if there were some sort of dark creatures attacking the ponies, Sora could easily dispatch them with his combat abilities.