Years after its release, Yu Yu Hakusho remains one of the most popular and beloved anime series of all time. Known for its cast of unique and genre-defining characters, musical score, and powerups, it's a series that inspired generations of industry creators and fans around the world.

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But almost 30 years after its release, there are still questions that linger in the minds of adoring enthusiasts. With this list, well be taking a look at 5 mysteries surrounding the series it took years to uncover, and 5 we never solved.

10 Solved: How is Yusuke So Powerful?

Since the beginning of the series, it's made abundantly clear that Yusuke exists as an extremely powerful spirit detective. He frequently comes out on top of his encounters with otherworldly demons, when he is merely a teenage human. It isn't until later in the series that we begin to understand why he was so powerful in the first place. Yusuke happens to be a half-human/half-demon hybrid. There are only a few demons in existence more powerful than him.

9 Unsolved: Why are Kuwabara and Yusuke's uniforms different than the other students?

You probably noticed this issue yourself, but early on in the series Yusuke, and Kuwabara are seen during various times in their daily school lives. When seen around other students of the school, they stand out in stark contrast because of the colors of their uniforms. Yusuke wears a dark green jumpsuit and Kuwabara wears a light blue one. The question remains to be answered, why do their uniforms appear differently from the other students of the school? It could have just been a technique employed by the animators to differentiate the main characters from the background characters, but we may never know.

8 Solved: Does Kuwabara Have Any Other Family?

If you've watched Yu Yu Hakusho, then you are familiar with Shizuru, the older sister of Kazuma Kuwabara. She is a major supporting character of the series, especially early in the story.

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Most fans were left wondering if Kuwabara had any other family members apart from Shizuru. This question remained unsolved throughout the run of the anime series. Not until the last volume of the manga did we find out that Kuwabara's father exists, and that he is a cooler, more laid back version of his son.

7 Unsolved: Whatever Happened To Hiei's Jagan Form?

One of the first major arcs of the series begins with Hiei and the Jagan Eye. The Jaganshi form is a transformation, which Hiei can utilize after he has been implanted with the Jagan Eye. The ancient artifact is embedded in the user's forehead, granting the user incredible mental powers. The Jaganshi form appears in Hiei's first fight with Yusuke. While it remains powerful, the form comes with its weaknesses, since Hiei has many eyes around him. If he is blinded, he will be crippled. Considering the Jagan Eye played a major point in his character arc, it's surprising that it only makes another brief appearance in the movie, Poltergeist Report.

6 Solved: When Did Hiei And Kurama Meet?

Throughout the story, the relationship between Hiei and Kurama remains widely known for its long and storied history. Kurama, a master thief and A-class demon who survived by retreating into the human world, and took host in the body of an unborn baby. Hiei, a fire demon cast out as an infant and raised by bandits. But it wasn't until the release of the two-shot manga that we learned about their true backstory. The two originally met when they were 14 years old, one year before they defeated the demon Eight-Hands.

5 Unsolved: Why Couldn't Kurama Use Both Demon And Spirit Energy?

Kurama in Yu Yu Hakusho holding a flower.

Towards the end of the series, Yusuke utilizes both his demon and spirit energy. This is possible in part due to his half-demon and half-human heritage. Kurama endures as one of the most powerful demons in the series, but his strange origin leaves much room for mystery.

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The question waits to be answered if Kurama can employ both his demon and spirit energy. Considering he took over a human baby's body as his host, it seems possible that he would tap into the same energy as Yusuke.

4 Solved: Who is Jorge?

Jorge (Yu Yu Hakusho) mad

If you've read the manga before you watched the anime then you would surely be confused by the presence of Jorge, Koinmas reluctant assistant. Jorge is a giant, blue ogre with a horn centered in the middle of his forehead and blonde flowing hair, notable for his comical personality. He makes no appearance in the manga, and his purpose in the series was a curious one. The true nature of his existence isn't revealed until the second to last episode of the show. Ultimately, he unveiled himself as the series's narrator.

3 Unsolved: How did Hiei Know What Yukina Looked Like?

Hiei holding Yukina in Yu Yu Hakusho.

The relationship between Hiei and Yukina is a strange one considering Hiei's backstory. Shortly after his birth, he was cast out from his village for being a half fire demon in a village of ice demons. He didn't know the existence of his twin sister until his surgery to receive the Jagan Eye. But strangely, he exhibits clear memories with her as a child even though he was an outcast when he was a baby. This could be a massive plothole issue that was never addressed or a missing piece of Hiei's backstory.

2 Solved: Is Keiko and Yusuke's Relationship True Love?

While their love isn't at the same level as some other famous anime couples, Keiko and Yusuke are the major romantic relationship of the series. There is never a clear delineation in the series where their love begins. Whether it was an event that caused it or love at first sight. But the manga ends up giving us a little bit more information than the series, detailing their close and somewhat romantic relationship since childhood. We all continue to root for Yusuke and Keiko as a symbol of true love long after the series's end.

1 Unsolved: Will The Series Ever Return?

Team Urameshi from Yu Yu Hakusho

Yu Yu Hakusho remains one of the most popular animes today, spawning multiple movies, OVAs, books, video games, and CDs. But there has always been one lingering question regarding the series: will it ever make a return? This is a question that's only half resolved. We continue to get new content in relation to the series, such as OVAs and movies. We are even getting our first live-action version of the series. But we still don't know if we will get a true continuation of or successor to the anime series.

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