Masashi Kishimoto's Naruto is one of the most popular mangas in the world, even after its conclusion. The manga ran in Shueisha's Weekly Shounen Jump from 1999 to 2014, which is very impressive. One of the things that made Naruto prominent was Kishimoto's poignant storytelling.

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For the shonen genre, it offered something unique, and the fans couldn't help but fall in love with the complexity and detail of it. However, even a series as polished as Naruto has some things that were left unexplained, and others that we simply can't find answers to. Here are 10 Naruto storylines that were left unresolved.

10 Naruto's Truth-Seeking Balls

Naruto Uzumaki Truth-Seeking Balls In Six Paths Sage Mode

The Truth-Seeking Balls are gained when one awakens to Six Paths Senjustu. During the Fourth Great Ninja War, Hagoromo Otsutsuki gave half his chakra to Naruto, which led to him awakening Six Paths Sage Mode. Naruto had access to 9 truth-seeking balls in total, but he kept losing them over the span of the war. In his fight against Sasuke, he was left with 3 of these balls, but they suddenly vanished, never to be seen again. Even in Boruto, Naruto is without the truth-seeking balls, and it was never explained how he lost the last three.

9 The Six Paths Sage Mode

Naruto Uzumaki Six Paths Sage Mode smiling

Naruto Uzumaki had gained several forms over the course of the story, and his strongest form is the Six Paths Sage Mode. He awakened it during the Fourth Great Ninja War. In appearance, it looks a lot like the Nine-tails Chakra Mode, but there are key differences. One of them is that where the Nine-tails Chakra Mode gave a yellow hue to Naruto's face, the Six Paths Sage Mode didn't. However, after the 4th Great Ninja War, Naruto's Six Paths Sage Mode looks akin to the Nine-tails Chakra Mode, which has led to mass confusion among the fans. Why this decision was taken is something that Kishimoto never bothered to explain to the fans.

8 Madara's Mangekyo Sharingan Ability

Madara Uchiha was a legendary figure from the old era in Naruto. Along with his brother, Izuna, he was the first person to awaken the fabled Mangekyo Sharingan. As seen in the series, each Mangekyo Sharingan has a set of abilities. Itachi's Mangekyo Sharingan had Amaterasu and Tsukuyomi, while Sasuke's had Amaterasu and Flame Control.

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When it comes to Madara, his Mangekyo Sharingan didn't have any such abilities. All he could do was use the third ability of the Mangekyo Sharingan, called the Susano'o. His other Mangekyo abilities will remain a mystery forever.

7 Sasuke's Rinnegan Powers

Sasuke Uchiha Rinnegan Powers

Sasuke Uchiha gained the strongest of the three great eyes, the Rinnegan, during the 4th Great Ninja War. The Rinnegen is said to have lots of magnificent powers, such as the Six Paths techniques, the ability to produce chakra rods, and, last but not the least, the ability to use the Outer Path. In Sasuke's case, some of these abilities don't seem to work, though. Sasuke has only ever used two of the Six Paths, and he has never displayed the ability to create the black receiver rods either. The Six Paths techniques are extremely powerful when used properly, and even the chakra receivers can be used as a lethal weapon. Why Sasuke has never thought about using them is something that nobody can explain.

6 Hiruzen Sarutobi's True Power

Hiruzen Sarutobi, the Third Hokage, in his younger days in Naruto.

Hiruzen was the Third Hokage of Konoha in Naruto. He was known as the God of Shinobi, and the Professor as well. It is said that in his prime, Hiruzen was the strongest of all the Hokage who came before him, which includes Hashirama Senju as well. Hashirama himself was an extremely powerful figure, so could Hiruzen really have been stronger than him? Unfortunately, the answer to that will elude the fans forever, since Hiruzen's power was never revealed in the entire series. Even when he was reanimated by Orochimaru, he came back as an old man, once again way beyond his prime.

5 Itachi Uchiha's Illness

Itachi Uchiha was one of the most prominent figures throughout Naruto. As Sasuke's elder brother, he played a massive role in his life and in the formation of his 'ninja way'. Itachi was one of the strongest characters in the entire series, which is an undisputed fact. However, he never fulfilled his potential because of a terminal illness that he contracted. This mysterious disease kept him from reaching his full potential. But, what exactly was this disease? Masashi Kishimoto never explained to the fans how Itachi got sick, what his disease was, and why he, of all the Uchihas, had this strange illness. Even though Itachi eventually got his own light novels, his disease still remains a big mystery.

4 Hashirama's Sage Mode

Hashirama in Sage Mode in Naruto.

Hashirama Senju was the strongest shinobi of his generation and the creator of Konoha. He was an extremely powerful Kage, and his sheer strength had earned him the title of 'God of Shinobi.' Hashirama's biggest weapon was his Wood Release Ninjutsu, coupled with his sage mode. In the entire series, we've seen three main sage regions, which includes Mount Myoboku, Ryuchi Cave, and Shikkotsu Forest.

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Naruto Uzumaki learned his sage mode from Mount Myoboku, while Kabuto learned his from Ryuchi Cave. Hashirama's sage mode is the only one that isn't affiliated with a known sage area. It is speculated that he learned this technique from Shikkotsu Forest, but it has never been confirmed. The fans would love to know the answer to this, but for now, it remains unresolved.

3 Might Guy's Injury

Might Guy Opens The Eight Inner Gates with an angry expression on his face

Might Guy went all-out against Madara during the 4th Great Ninja War. To protect the world, and save the next generation of ninjas, he opened all eight inner gates and fought Madara to his last breath. After this mind-blowing fight concluded, Madara survived, while Guy lost his leg and almost lost his life as well. Thankfully, Naruto arrived with his newly awakened powers and restored Guy's life force, which saved him from death. Strangely enough, Naruto didn't heal his shattered leg. Just moments later, Kakashi Hatake lost his eye to Madara and Naruto was able to restore his eye with his abilities. Why he didn't do the same for Might Guy is something that can't be explained at all.

2 Itachi's Ethereal Weapons

Itachi susanoo

Itachi Uchiha possessed the Mangekyo Sharingan which gave him the ability to utilize the absolute defense, Susano'o. Interestingly, his Susano'o was very different from the rest as he had acquired two ethereal weapons, which made it invincible. He had the Totsuka Blade, which was capable of sealing anything it pierced in a Genjutsu world and the Yata Mirror, which could reflect any attacks. Where Itachi found these weapons, and where they went after his death remains unknown to date. In the past, Orochimaru tried looking for them but failed because Itachi had already gained access to them before he did.

1 The Otsutsuki Clan

Finally, the Otsutsuki Clan is another big mystery that's never been resolved in Naruto. This clan of aliens was introduced to us towards the end of the series. Its pure-blooded members include Kaguya, Kinshiki, and Momoshiki, among others. From what we've been told, the Otsutsukis are well and alive. However, it is unknown where exactly this clan is located, who heads it, and how many members it has. They could be a huge threat to Earth, so it feels odd that no focus has been thrown on them so far. But, the Boruto series is continuing right now, so hopefully, one day, we'll get an answer to this question.

NEXT: Naruto: 10 Hidden Details About Sasuke Everyone Missed