Isekai is arguably the most popular theme of the last decade, at least when it comes to anime. Each season includes a few shows that involve protagonists being sent to other worlds, with each year producing 20+isekai anime. That is a lot of content, but the genre is largely known for quantity rather than longevity or quality. Most series only receive a single season of 12 or 13 episodes, and they are typically forgotten once the next lineup debuts. A small selection of anime receive sequels, but they very rarely get more than one.

A tiny, tiny percentage of isekai anime last for years, producing multiple seasons and even the occasional movie. While not reachingOne PieceorNarutonumbers, these shows captured the cultural zeitgeist enough to turn them into relatively monumental properties, allowing them to produce more than 50 episodes. Short shows certainly have their place, but there is something special about agreat long isekai animethat can keep viewers engaged for months. Let’s highlight the best ones.

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Here are some notes and criteria:

Even more than a decade after its debut,Log Horizonholds up as one of the best-written isekai anime, particularly ones set in a game. Thousands of Elder Tale players find themselves unable to log out of the MMORPG, and they have to gradually work to craft a society that satisfies the needs of both themselves and NPCs. The anime has fantastic world-building, along with a great mage protagonist who focuses on strategy rather than brute strength. The first season compares favorably to pretty much any other isekai anime, and it blends adventure, comedy, action, and social discourse incredibly well.

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Log Horizonhas three seasons, which sounds great on paper; however, the sequels are polarizing. While Satelight handled the first season, Studio Deen took charge of the two follow-up entries, and they are notably all over the place in terms of quality. Season 2 has great moments and a top-notch final arc that revolves around raiding, but it also has a rough 8-episode stretch that follows an irritating group of characters. Season 3 is mostly just forgettable.

In terms of sheer popularity,Sword Art Onlineis the biggest isekai anime of all time, and by quite a margin. However, the story only falls under the “trapped in a game” subgenre some of the time, as there are a couple of arcs where Kirito can log off without much issue.

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While named after the game that serves as the setting for the first 14 episodes,SAOchanges its world with each subsequent arc, resulting in an inconsistent journey that has impressive highs (Aincrad and Alicization) and frustrating lows (Fairy Dance and Phantom Bullet). Some sense of stability is maintained by the presence of Kirito and a few girls, but they are held back by some pretty terrible writing at times. Fortunately,SAO: Alicizationis by far the franchise’s best series and covers nearly 50 episodes on its own.

An original anime that debuted a few years before isekai became inescapable thanks toSword Art Online,Kibahas aged reasonably well and still feels fresh since, for the most part, it avoids the tropes that have come to define the theme. Summoned to a new world and tasked with collecting six spirits, Zed is the star of the show and arguably the main thing that setsKibaapart from the crowd, as he has a far more cruel and pragmatic outlook on life than traditional isekai protagonists.

Fushigi Yuugi

While never reaching very impressive highs,Kibais consistent, withMadhouse’s stamp of qualitybeing obvious throughout the entire show. Although leaving room for a sequel, the story ends on a rather satisfying note, which is not something that can be said for many isekai anime.

Aminor shojo ’90s classic,Fushigi Yugiis a product of both its demographic and decade, which is hardly a bad thing. While she does not make the trip on her own, Miaka takes center stage and ultimately plays the role of the chosen one while in a fantastical Chinese empire, and her main goal is to bring together seven great warriors. Naturally, a reverse harem develops between Miaka and the male heroes, although her main romantic partner is obvious from the start.

King From Now On

Fushigi Yugiis relentlessly charming, as long as the viewer is not impervious to antiquated visuals and character archetypes that have grown a bit out of fashion in the last few years. The anime has a likable and relatable protagonist who grows quite a bit throughout the story, along with an antagonist (Yui) who is just as interesting. The setting is also pretty great.

A real blast from the past that is known by a few different names,Kyo Kara Maohis a rare example of an isekai anime with more than 100 episodes that tells a uniform story rather than being divided into almost standalone arcs. Yuri Shibuya gets his face stuffed in the toilet and, somehow, ends up in another world. If that was not strange enough, he learns that he is the demon king, which instantly puts a lot of responsibility on his shoulders.

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Although not devoid of bursts of action,Kyo Kara Maohis mainly an adventure comedy that follows a likable cast of characters as they slowly attempt to make the demon kingdom a more welcoming place for everyone. The anime does become a bit repetitive after a while, but it never stops being entertaining or throwing outboys' lovejokes.

Digimon,technically, has over 500 episodes, but onlyDigimon Adventure 02andTriare set in the same universe as the original show. There is also the 2020Digimon Adventurereboot, which lasted for 67 episodes. The 1999 version is better, though.

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Digimon Adventureis not synonymous with isekai, perhaps due to most people watching the series when they were kids and did not know about the genre. Nevertheless, the 1999 classic 100% fits the bill, with the Digidestined finding themselves trapped inthe Digital World. Nostalgia aside,Digimon Adventureis an impressive kids' anime that incorporates just enough mature elements to have something to offer older viewers.

The original series can be watched in isolation. In 54 episodes,Digimon Adventuremanages to accomplish quite a lot and maintains a pretty quick pace, with none of the arcs overstaying their welcome.Digimon Adventure 02is messier and does not reach the same heights as its predecessor, although it has plenty of decent episodes. While a different beast from its much-older predecessors,Triserves as a beautiful conclusion to this universe and these characters.

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An all-around delightful romp,Welcome To Demon School! Iruma-kuncomes very close to being the full package. The anime has a huge roster of lovable characters, a vibrant and distinct setting, reliable and varied humor, and decent fight sequences. While somewhat childish at times, the story also knows when to take itself seriously, including a couple of action-driven arcs that slip seamlessly into battle shonen territory.

Iruma has led a difficult life, mainly due to his terrible parents. Therefore, he is not that surprised when they sell him to a demon, who winds uptaking him to a world filledwith creatures who just love to eat humans. Fortunately, once he starts attending Babyls School and makes a few quirky friends, Iruma quickly realizes that he enjoys the demon world way more than Earth.

That Time I Got Reincarnated as a Slime TV Series Poster

While season 2 marks the show’s peak so far,Welcome To Demon School! Iruma-kunis fun from start to finish, and the story goes through enough progression to resist the development of stagnation. Season 3 threatens to overstay its welcome at times, but it also has the best action in the series.

Thebest long isekai animeare usually forever expanding, forcing the characters to either change their thinking or adopt more ambitious goals.Overlordis among the better examples of this type of evolution, as Momonga initially only wants to learn about the MMO-like world that he finds himself trapped in.

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During the first season, he is driven by a desire to fortify the Great Tomb of Nazarick’s place in the world, ensuring the safety of the NPCs who serve him. However, as the story progresses, Momonga becomes Aing Ooal Gown, a proper “final boss” persona who establishes a new kingdom that threatens the status quo, all the while his previous life’s humanity gradually becomes less of an influence on his current actions. The world also adapts to his presence, arguably transforming itself from high todark fantasy.

Working as something of a companion piece toOverlord,That Time I Got Reincarnated as a Slimeessentially follows the same pattern, albeit with a protagonist who mostly acts on positive vibes and a desire to create a haven for all monsters. Rimuru starts as a weak slime who can pick up the skills of other creatures, which allows him to quickly gain power and become a beacon for outcasts who do not have a kingdom to call their own.

Although initially alighthearted adventure comedy,That Time I Got Reincarnated as a Slimepicks up a more mature tone as it begins to explore the political climate of the world, an endeavor that largely dominates season 3. While this shift comes with a slower pace and an emphasis on dialogue over action, the writing is generally quite good, as is the gradual introduction of influences that oppose Rimuru’s way of life.

Although a spin-off,The Slime Diariesis still a must-watch for fans, as it shows the day-to-day routines of Tempest’s citizens.

As great as the bestlong isekai animeare, they are mostly predictable. If somebody enjoysSlimeseason 1, they will likely love the sequels.Re:Zerois an exception – all three seasons are fantastic, but also widely different.

Season 1 is split into (relatively) short arcs that prioritizeSubaru’s descontruction and development, all the while introducing the main supporting characters and establishing the world’s rules. Season 2 primarily revolves around a single storyline and setting, with Subaru taking a bit more of a backseat in favor of characters like Emilia and Beatrice. This season prioritizes dialogue over pretty much everything else, and some scenes even venture into horror territory. Finally, season 3 pushes action to the forefront, delivering a (relatively) fast-paced arc that almost seems battle shonen-esque at times.

Re:Zerois both the best isekai anime of all time and one of the most polarizing, as a viewer’s opinion on the show could change widely from one episode to the next. Even if that can create an uneven overall experience,Re:Zerois nevertheless constantly pushing the envelope and trying something new.