It's likely that Naruto's chakra control and power would develop in new and unexpected ways. Black Zetsu might introduce him to strange chakra - based abilities that are not part of the normal ninja training. This could give Naruto an edge in combat, but it also might make him a target. Since Black Zetsu has his own motives, Naruto could be dragged into some dangerous and complicated situations that he may not be fully prepared for.
He may develop a more calculating side. Black Zetsu is all about manipulation. Naruto could start thinking several steps ahead in a more devious way. For example, he might start using people's weaknesses against them, which is completely against his original nature. This change in personality would likely cause a rift between him and his friends who know him as the always - honest and straightforward Naruto.
Well, one possibility could be that Zetsu imparts some unique and dark jutsu to Naruto. Maybe Naruto starts to learn stealth and subterfuge skills from Zetsu, which are different from what he learned at the ninja academy. This could lead to Naruto having an edge in certain battles where traditional ninja skills aren't enough.
There could be internal antagonists within Naruto's own village. Some of the more conservative ninja in the village might not trust Naruto's new - found skills and powers obtained from Zetsu. They could try to undermine Naruto or even attempt to exile him, fearing that he has been corrupted by Zetsu's teachings.
In a fanfic where Naruto is trained by Zetsu, the story could take an interesting turn. Zetsu has knowledge of the Akatsuki and their secrets. Naruto could learn about the organization from the inside out. This knowledge could help him in his quest to bring peace. He might also gain some physical enhancements. Zetsu is quite durable in his own way, and Naruto could inherit some of that sturdiness. This would make him an even more formidable opponent in battles against strong foes like Pain or Madara.
His relationship with Sasuke might be affected. Naruto might approach Sasuke differently, with new strategies learned from Zetsu. He could be more secretive about his intentions towards Sasuke, which might either make Sasuke more curious or more distrustful. With his friends in Konoha, they might be a bit wary of Naruto at first because of his new training source. But once they see that Naruto is still on their side, they would support him.
If Naruto has Black Zetsu in the fanfiction, it can change the power dynamics. Black Zetsu might try to use Naruto's power for its own ends. Maybe it convinces Naruto to use his power in a way that seems good at first but actually has hidden motives. This could lead to new alliances and enemies forming in the Naruto universe. For instance, some villages might see Naruto as a threat now that he's being influenced by Black Zetsu.
Black Zetsu's story in Naruto is quite the tale. He was an entity that had been around since ancient times. He had an in - depth knowledge of the ninja world's history and used this to his advantage. He was the driving force behind many of the conflicts in the Naruto series. For example, he caused a rift between Sasuke and Naruto at times. His true nature was only revealed towards the end of the series, which was a shock to many characters. He was a master of manipulation, using the desires and weaknesses of others to achieve his ultimate aim of bringing back Kaguya.
One key event was his deception of Madara. He made Madara think he was his ally while actually setting him up for Kaguya's revival. Another was his influence on Obito. He pushed Obito to do things that served his purpose. Also, his role in the Fourth Great Ninja War was significant as he was behind many of the unexpected turns in the war.
One idea could be that Naruto discovers Black Zetsu has been secretly influencing some of the village's decisions all along. Naruto then has to find a way to expose Black Zetsu's actions without causing chaos in the village. Another plot could involve Black Zetsu trying to manipulate Naruto's newfound power for its own evil purposes. Naruto has to resist and use his own willpower and the power of friendship to overcome it.