The OC could be a rescuer. They may arrive during the massacre and use their Otsutsuki - related abilities to save a few Uchiha. Maybe they have the ability to create portals and whisk some Uchiha away to safety. But this action could have far - reaching consequences, like drawing the attention of other dangerous forces in the Naruto world.
The Otsutsuki OC could be a catalyst. They might have some knowledge about the future or some power that the Uchiha want. This could lead to internal strife within the Uchiha clan as some members might be tempted to side with the OC for power, while others oppose it, which could be a contributing factor to the massacre.
In a fanfiction, the Otsutsuki OC could play the role of an investigator. They might be curious about the Uchiha's power and the reasons behind the massacre. So they start to dig deeper into the events. They could interact with various characters, such as Itachi or Sasuke, and their investigations could reveal hidden truths about the Uchiha, Konoha, and the Otsutsuki's connection to the whole situation.
One way is to make the Otsutsuki OC a hidden observer during the Uchiha massacre. They could be there to study the Sharingan or the power dynamics within the Uchiha clan. For example, they might be interested in how the Uchiha's emotions, like hatred, are related to the power of their eyes. Another way is to have the OC be a factor that somehow influences Itachi's decision. Maybe they offer him a different option or some knowledge that makes him rethink his actions, but in the end, the massacre still occurs due to the complex web of political and clan - related reasons in the Naruto universe.
The Otsutsuki OC might be an unexpected bystander during the Uchiha Massacre. For example, they could have been on a different mission in Konoha when the massacre started. They might then decide to get involved, either to save some Uchihas out of a sense of justice or because they see potential in the Uchiha bloodline for their own purposes. So, they end up interfering with Itachi's plan and creating a whole new set of consequences for the story.
Well, the OC might try to prevent the Uchiha Massacre. Maybe they have a different view of the Uchiha compared to the Konoha leadership. They could try to convince the Uchiha to flee or negotiate with Konoha. If they have unique powers or knowledge, they could use it to expose the real motives behind the planned massacre and create a situation where the Uchiha are spared. This would completely rewrite the story of the Uchiha's downfall.
To create a compelling OC, start with their appearance. For this type of fanfiction, you could give them features that are a blend of the Uchiha and Otsutsuki. For example, the dark hair of the Uchiha but with the strange markings of the Otsutsuki. Then, focus on their goals. What do they want? Is it to bridge the gap between the two clans? Or to rise above them? Their relationships are also crucial. How do they interact with existing Naruto characters? Do they make friends easily or are they more of a loner? And don't forget about their weaknesses. A character with flaws is more relatable and interesting.
One popular theme is the struggle between the Otsutsuki and Uchiha powers within the Naruto universe. The OC (original character) often has to navigate the complex politics and power dynamics of these two powerful clans. Another theme is redemption. For example, an OC Uchiha who has to overcome the dark past of the clan, like the massacre, and find a new path in the world filled with Otsutsuki threats. Also, themes of friendship and loyalty are common. The OC might form unlikely alliances with characters from different clans in order to face the common Otsutsuki enemy.
She could survive by being away from the village during the massacre. When she returns, she is shocked. She decides to investigate the real cause of the massacre. Along the way, she discovers some dark secrets about her clan and the village. This knowledge gives her a new purpose, and she uses her Uchiha powers to bring the truth to light.
The plot could involve Kaguya's influence on the OC. Maybe the OC is a new being in the Naruto universe and Kaguya sees potential in them. For example, she could want to use the OC to regain her full power or to create chaos in the shinobi world again. The OC might initially be in awe of Kaguya but then realize her true intentions and have to fight against her.
He could be a warrior. With his combat skills, he'd be great in the battles for the Iron Throne. He might side with a particular house and use his powers to protect them.
She could be a mentor figure. Since she's from the Uchiha clan, she might have a deep understanding of things like chakra control and ninja techniques specific to the Uchiha. Naruto could learn a great deal from her.
He could be a rebel. Tired of the Bolton family's traditional ways, he might try to change the family's reputation. He could be a force for good in the North, protecting the smallfolk from the usual Bolton brutality.