One of the most popular and controversial anime series of the last decade, Sword Art Online is a show that's intensely divisive, with fans and critics both being equally passionate. Viewers range from the hardcore advocates who praise it as a revolutionary title in the isekai genre to vocal critics who are completely baffled as to how and why the show has gained so much popularity. So how did Sword Art Online's popularity become so controversial in the anime community?

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What Is Sword Art Online?

Kazuto and Asuna back to back with Silica on the left and Lisbeth on the right.

Sword Art Online follows protagonist Kazuto Kirigaya, a high school otaku who loves video games. After logging onto the VRMMORGP "Sword Art Online" and taking on the avatar handle "Kirito," the boy soon discovers he's trapped in the virtual world with no way to escape. The series follows Kirito and his friends' adventures as they attempt to escape SAO, as well as other video game universes in the anime's later seasons. Though the video games change throughout each arc, the blurring of lines between video games and reality is ever-present.

The anime is based upon a light novel series by Reki Kawahara that shares the same name. Since the anime's release in 2012, Sword Art Online has produced additional seasons and an original movie.

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Hardcore Sword Art Online superfans, who've stuck with the series for all four seasons, praise the show's evolution from season to season. Each season has improved upon the last, a statement reflected in Season 4's current score of 7.58 on MyAnimeList. Plus, since the show's main focus changes every arc, dedicated fans love how the stakes are constantly shifting and raising for Kirito and his friends. Additionally, as an isekai, Sword Art Online features a number of fight sequences that, even during some of the show's weaker seasons and arcs, are inarguably exciting to watch and are beautifully animated.

Finally, Kirito's journey as an introvert in the real world to a praised video game hero in the virtual one is a characterization that's appealing to a wide range of audiences. Viewers sympathize and see themselves within Kirito's story, which may explain why so many fans have stuck with the anime for so long. In Season 1, Kirito was introduced as a lonely homebody who didn't have many friends in real life and spent most of his day on the computer. However, because of his experiences meeting people in video games, his real-life persona has completely changed. He now has a huge group of friends (most of whom are beautiful ladies) and, if he ever escapes the Underworld, has plans to attend a prestigious American university with his girlfriend, Asuna.

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Sao Is as Controversial as It Is Loved

Ronye and Tiese bound and gagged prior to Humbert's sexual assault on them.

While hardcore fans have a long list of reasons why they've supported the show for almost a decade, critics have also justified their dislike with an equally lengthy list of cons.

From a purely technical standpoint, Sword Art Online's earlier seasons suffered from bad writing. The pacing was inconsistent, especially during the anime's initial arc, "Aincrad." Episodes quickly skipped over months and years, with minimal exposition to make up for the lost time. This was mostly due to the anime's rushed attempt to cover multiple story arcs over the course of 25 episodes in Season 1 and 24 in Season 2. As a result of this rushed style of writing, characters had little time and space to develop, leaving many fans critical of their shallow personalities, as well as the show's general lack of focus.

Luckily, most of these technical issues have been fixed since Sword Art Online's third season premiered in 2019, and have remained consistent through Season 4. Despite these technical fixes, there is another major issue that Sword Art Online critics have been vocally protesting for almost a decade now.

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Eugeo holding a sword on the left with Kazuto in the center and Alice Zuberg facing right.

Since Season 1, every season of Sword Art Online has featured one scene where a female character is sexually assaulted, usually by a male villain character. Viewers have been incredibly vocal about their disgust over the exploitative nature of this repetitive plot device for years now. Yet, despite acknowledgment and apologies from Reki Kawahara, even the most recent season in 2020 featured an incredibly graphic scene. Combined with SAO's continued inclusion of fanservice-style portrayals of its female characters, it's not a great look for the popular isekai.

Whether viewers think Sword Art Online is the greatest anime franchise ever made or detest it with a passion and can't understand why it's become a global success, one thing is certain: Sword Art Online is a popular show and its legacy will remain for years to come.