Merlin's character may become more confident. Being raised by dragons, he has a different source of wisdom. He might be more fearless in the face of danger compared to his canon counterpart. For instance, when facing Morgana's schemes, he won't be as hesitant.
One interesting plot could be Merlin's discovery of unique magical powers that are a result of being raised by dragons. For example, he might have an innate ability to communicate with all magical creatures, not just dragons. Another could be his struggle to fit into the human world while having such a different upbringing. He may face challenges in understanding human customs and politics.
Well, in many fanfictions, it could be Igneel and another dragon like Metalicana. Igneel is Natsu's adoptive father in the original series, and Metalicana is Gajeel's dragon. Combining them in a fanfiction as Natsu's caretakers could lead to some really interesting character dynamics.
Merlin's character might develop a sense of loyalty to Nimueh at first. Since she raised him, he would see her as a mother figure. But as he grows and experiences more of the world, he starts to question her motives. This leads to a more complex character as he has to decide where his true loyalties lie.
Eragon would probably have a different view on power. Since he was raised by dragons, he would see power as something to be respected and used sparingly, as dragons do. He may also be more fearless, as dragons are often seen as powerful and fear - inspiring creatures. His communication skills with dragons would be far superior, and he might struggle to communicate as effectively with humans.
Igneel could be one of the main dragons. Since he has a connection with Natsu in the original story, it would make sense for him to be among the dragons raising Natsu. Another could be Metalicana, as he is also a well - known dragon. Grandine might also be there, considering her importance in the Fairy Tail universe.
Merlin is the main human character. The dragons, such as Aithusa, could be important characters. Aithusa, being a white dragon, might have a special role in the story. Additionally, Gaius could be a significant character. He might be worried about Merlin living with the dragons at first but then come to understand the importance of it. His wisdom could also play a part in guiding Merlin in his new life among the dragons.
One possible plot could be that Merlin discovers a hidden dragon lair where he is accepted as one of their own. He learns dragon magic and uses it to protect Camelot in ways he couldn't before. Maybe he even rides the dragons into battle against powerful dark forces.
In a 'Harry Potter raised by Merlin' fanfiction, the plot could be really interesting. Merlin, being an extremely powerful and knowledgeable wizard, would raise Harry in a secluded place perhaps. He would teach Harry not only spells but also the ethics and history of magic in a very detailed manner. Harry would grow up with a different set of values compared to the ones he would have if raised by the Dursleys. His view on dark magic might be more nuanced as Merlin has seen the rise and fall of many dark wizards. Also, his relationship with other magical creatures would be different. For instance, he might befriend centaurs or merpeople in a more profound way because Merlin could introduce him to them in a respectful and understanding way. This would make his adventures at Hogwarts and beyond quite different from the original story.
Well, one possibility is that Naruto would grow up with dragon - like powers. He might be able to breathe fire or have super strength. And his view of the ninja world would be very different, as he was raised in a dragon's lair rather than the Hidden Leaf Village.