Just when you think that there aren't any surprises left in the world of Naruto, you come across an article like this. For years, Masashi Kishimoto's seminal ninja series was one of the most popular franchises in the world. The more well-loved a series is, the more fans will try to learn everything they can about its world and characters.

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Indeed, there are very characters as mysterious and enigmatic as Sasuke Uchiha. We imagine that most of you die-hard Naruto fans probably think you know Naruto's rival like the back of your Cursed Seal. But we promise that at least one of the following ten facts will catch you off guard.

10 He Wasn’t Originally A Series Mainstay

Imagining Naruto without Sasuke is trying to picture Breaking Bad without Jesse Pinkman - or the Buu Saga without Goku! Incidentally, all of these characters weren't initially supposed to be as prominent as they ended up. The same goes for Sasuke Uchiha - the yin to Naruto's yang.

According to legend, Masashi Kishimoto’s editor suggested he create a rival for Naruto. Kishimoto initially wanted the series to only focus on Naruto - who most of you might know was supposed to be a walking, talking fox! But with a push and a nudge, Kishimoto set out to create one of the most memorable characters in animanga.

9 His Name Comes From Manga & A Folk Hero

The legendary ninja Sarutobi Sasuke.

One of the first things Masashi Kishimoto needed to do was name Naruto's rival. Ask any writer and they'll tell you how difficult it can be to find a name that's just right for a character - cue the Pacha memes, please.

Eventually, Kishimoto gave Sasuke Uchiha his name based on Sanpei Shirato’s eponymous manga and the folk hero Sarutobi Sasuke. Shirato's Sasuke manga is fairly rare, but we can tell you it's nothing like Naruto. As for Sarutobi Sasuke, imagine folk heroes like Davy Crocket or Gordon Lightfoot if they were samurais and you've got the gist of it.

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8 Hiei Is Another Big Influence On Sasuke

Finding the right name for Naruto's rival was a hard enough battle in and of itself. But eventually, Kishimoto had to decide what sort of personality Sasuke would have. To find inspiration, Kishimoto popped in one of his all-time favorite shows - Yu Yu Hakusho.

Legend has it that Kishimoto initially wanted to analyze the dynamic between Yusuke and Kuwabara - as Kishimoto never created a series with a rivalry at its core before. However, it was Hiei that Kishimoto found himself drawn to the most - inspiring Sasuke's brooding demeanor and overall dark powerset.

7 Kishimoto Struggled The Most When Designing Sasuke

With Sasuke's name and character in mind, Kishimoto had but one obstacle left before him - finally designing this brooding antihero. Word has it that Kishimoto had more trouble designing Sasuke than any other character in the series; he'd often draw his face looking far too old for his age, making the young shinobi look like a grown adult!

Kishimoto also initially drafted an incredibly elaborate costume for Sasuke - one that featured numerous belts and straps in places they needn't ever be. However, Kishimoto soon realized how taxing this design would be to redraw over and over - eventually simplifying it into Sasuke's first blue and beige costume.

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6 Sasuke First Appeared In Chapter 1, Not Chapter 3.

Naruto-run over to any fan of the series and ask them when Sasuke first appeared. Most, if not all of them, will cite chapter 3 of the first manga series - aptly titled 'Enter Sasuke!!' for good measure.

In reality, Sasuke made his first appearance much earlier in the series - on page 13 of chapter 1. Look closely at the people sitting behind Naruto in the bottom left panel. In the upper left corner is a ninja with shades, just chilling. But directly behind Naruto is none other than Sasuke Uchiha - sitting by himself and no doubt fantasizing about killing Itachi.

5 Kishimoto’s Assistant Creates A Sasuke Spin-off Series.

Many of you might not know this, but Boruto isn't the first spin-off in the Naruto franchise. Years ago, Masashi Kishimoto's assistant - Kenji Taira - created a few spin-off manga based on popular characters from the series.

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Sasuke is the second Naruto character to receive a spin-off series, the first being Rock Lee. In both mangas, characters have adorable chibi designs and embark on humorous and whimsical adventures. Taka also comes along for the ride - flipping Sasuke's frown all the way upside down!

4 Sasuke Is Ambidextrous (Or At Least Left-Handed)

Eh, this one probably won't come as too much of a surprise, as Sasuke's essentially a wunderkind. If we told you that Sasuke could pilot military aircraft, how many of you would take our word at face value?

When the Sage of Six Paths asked Naruto and Sasuke to raise their dominate hands, Uchiha lifted his left hand. This suggests that Sasuke is either left-handed or at least ambidextrous. If the latter is true, chances are he trained both his arms to have a fighting chance against Itachi if he lost either one.

3 Onigiri And Tomatoes Are Sasuke's Favorite Foods

Sasuke eating onigiri

Most of you probably know what Onigiri is, but we'll elaborate just in case you're new to the anime scene (or if you work for 4Kids TV.) Onigiri is a Japanese dish that consists of rice and seaweed. It's tart, super salty, and yet strangely satisfying.

Conversely, Sasuke vehemently hates soybeans and sweets. The sweetest thing he'll eat is a ripe tomato, likely excluding ketchup from his diet entirely.

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2 Thus Far, Sasuke's Completed 16 Ninja Missions

Sasuke Uchiha as an adult in front of a body of water in Naruto.

We always imagine overachievers like Sasuke having high marks in school - even if it's ninja academy! But to our shock, we learned that Sasuke hasn't completed very many missions in his career.

Seven D-rank missions, one C-rank mission, two B-rank missions, and six A-rank missions. As weird as it sounds, Sasuke hasn't finished any S-rank missions yet.

1 Sasuke Likes Long, Solitary Walks

Sasuke running in a forest

Well, what else did you expect Sasuke's favorite hobby to be? This man's default mode is austere and stand-offish, so we don't imagine he's much of a party animal.

No, Sasuke prefers to trail off by himself - undoubtedly humming 'Boulevard of Broken Dreams' as he thinks about his dark past.

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