How can the OC's personality affect the story in an 'oc wakes up as natsu fanfiction'?

Well, if the OC wakes up as Hayley Marshall, they could start to develop Hayley's independent streak. Hayley is used to relying on herself, and the OC would probably have to do the same in this new situation. Also, they might become more empathetic towards the werewolves and other supernaturals, as Hayley has a big heart for her kind. This could mean the OC starts to care more about the well - being of others in the supernatural world.

One possible plot could be that the OC wakes up as Natsu in a world where Fairy Tail is facing a new, extremely powerful dark guild. Since the OC has their own knowledge and personality, they might use Natsu's powers in unique ways. For example, they could combine Natsu's fire - based attacks with strategic thinking that is different from the original Natsu. This could lead to new and exciting battles and alliances within the Fairy Tail guild as they try to figure out why Natsu seems a bit 'off' but is also more effective in some ways.

The OC could have accidentally said or done something that made Natsu feel unwanted or unappreciated in Fairy Tail. For example, if the OC is a new member and got more attention than Natsu in a certain situation, it might have bruised his ego and led to his decision to leave.

Suppose the OC is extremely headstrong. In that case, they might take more risks in battles or in dealing with the Akatsuki. This could lead to different outcomes, like maybe they'd charge into a fight with Pain without waiting for backup, which would change the whole sequence of events in the story.

If the OP OC has a confident and adventurous personality, they might be more likely to explore the unknown areas of the Log Horizon world right away. They could be the first to discover new quests or hidden locations. On the other hand, if they're more cautious, they might take time to study the game world and its rules before making any big moves.

The OC could also be a very protective type. Since fire can be seen as a symbol of protection in some ways, they would use their Magu Magu no mi powers to safeguard their friends and family. They might be calm and collected most of the time but when danger approaches those they care about, their personality shifts to a more fierce and determined state. They would create barriers of fire around their loved ones and face the threat head - on.

One possible plot could be that the OC wakes up in the world of Hayley Marshall and has to quickly adapt to the supernatural elements. Maybe they first struggle to understand their new powers, if they have any. They could end up becoming friends with Hayley and helping her in her battles against her enemies. For example, they might assist in protecting the werewolf pack from a new threat in the area.

One way to develop the OC's dark side personality is through their relationships. For example, if they had a love interest before, have them start to view that person as a weakness and cut them off coldly. They could also start to enjoy causing pain or fear in others, whether it's physical or psychological. And as they go deeper into the Sith teachings, they become more and more power - hungry, willing to do anything to gain more strength in the Force.

Consider their upbringing. If they were raised away from the main Lannister stronghold, they might have a different set of values. Maybe they were raised by a kind - hearted servant who taught them to be more empathetic. So their personality could be a mix of Lannister pride and this new - found empathy. They could be conflicted between loyalty to their family and doing what is right according to their own conscience.

An immortal OC can also impact the plot by being a source of information. Having lived through so much, they know the secrets of the past, including things about the origin of chakra or the true nature of certain clans. This knowledge can be a driving force for the main characters' quests and can completely change the narrative as they uncover things that were previously hidden.