While it might have been within the past decade that isekai anime became a global phenomenon, the genre has existed for far longer than that; even in the 90s and 2000s, there was always an appeal to stories about characters being sent to other worlds because of their potential for escapism and fun fantasy action, and if one were to go back even further, the popularity of stories like Alice in Wonderland and The Wizard of Oz means that isekai has been a thing for well over a century.
For better or worse, isekai is one of the most enduring genres in not just anime but fiction as a whole, and with that level of longevity, there are plenty of stories that have made a name for themselves as definitive classics of the genre. However, while shows like Inuyasha, Digimon Adventure, and Aura Battler Dunbine are still held in high regard, many other classic isekai stories have all been forgotten, and with how great some of them were, that’s nothing but a shame.
Monster Rancher
While Pokémon and Digimon dominated monster-battling anime in the 90s, an oft-forgotten third contender was TMS Entertainment’s Monster Rancher. While the original Monster Rancher games tended to be light on story, the anime came up with an original narrative filled with fun action and an engaging cast of heroes and villains, and even someone who never played the games could get a lot out of it.
Monster Rancher never had the same sort of polish that made Pokémon and Digimon so popular, which is likely why it faded into obscurity by comparison, but the anime is still a fun action romp anyone can enjoy, and it more than earns its place as an iconic 90s anime, even if so few people remember it.
El-Hazard
El-Hazard-Cast
When it comes to forgotten 90s anime, few shows better fit the description than AIC’s El-Hazard. Despite how well it uses high-concept sci-fi in tandem with a goofy, yet surprisingly deep narrative, El-Hazard and its various spinoffs and alternate continuities never truly became a big hit, especially when compared to Hiroki Hayashi’s true claim to fame, Tenchi Muyo.
While El-Hazard never truly took off, it’s still a fun anime for its gorgeous visuals, stellar direction, and fun characters and worldbuilding that mostly hold up by modern standards. In many ways, El-Hazard can be seen as having laid the groundwork for the isekai harem anime that overrun the medium, so for better or worse, it did leave its mark on the world.
Sonic X
Sonic grinning and waving in Sonic X
Sonic the Hedgehog was once framed as taking place on an alien world, and that idea reached its peak with TMS Entertainment’s Sonic X. While Sonic X was mostly a retelling of some of the games with some original characters and stories, it’s still fun to see it all play out in animation, especially for the moments that differ from the games, like the expansion on Maria’s death and the iconic Dark Sonic scene.
From the Truck-kun to the Tempest Federation · Eight Questions How Well Do You Know Isekai Anime? “In another world — with my smartphone.”
🎯AincradDeath-game MMO
⏳Re:ZeroReturn by Death
🔮KonoSubaUseless goddess
🥻Tempest SlimePredator Skill
👻OverlordAinz Ooal Gown
01
The Japanese term “isekai” (異世界) is now the catch-all label for stories about ordinary people transported, summoned or reincarnated into a fantasy realm — from Sword Art Online to Konosuba to Mushoku Tensei. What does the word literally translate to in English?
✓ Correct! “Different world” or “another world.” The word breaks into i (different) + sekai (world). The genre traces back as far as 1990s OVAs (Vision of Escaflowne, Fushigi Yuugi, Inuyasha) but exploded in the 2010s thanks to Sword Art Online (2009 LN, 2012 anime), Re:Zero, KonoSuba, Overlord and the “Narou” web-novel ecosystem of Shōsetsuka ni Narō.
✗ Wrong. The answer is “Different World.” Isekai breaks down literally to “i” (different) + “sekai” (world). It’s now used as a publishing-industry shorthand for the entire genre of transported/reincarnated/summoned-hero stories that boomed across the 2010s.
02
Re:Zero — Starting Life in Another World’s protagonist Subaru Natsuki is a hikikomori who’s pulled into a fantasy kingdom and given a single, brutal supernatural ability: when he dies, time rewinds to a fixed checkpoint and he relives the same stretch of days, retaining his memories. Name this signature ability.
✓ Correct! Return by Death. Subaru’s ability is treated by Tappei Nagatsuki’s novels as a curse rather than a power — the Witch of Envy locks his memory of it (he physically cannot tell anyone he can rewind), and every “reset” means he genuinely dies. Re:Zero is widely credited with redefining the modern isekai psychological lane and remains one of the genre’s most acclaimed entries.
✗ Wrong. The answer is Return by Death. None of the other names are official. Tappei Nagatsuki’s web-novel-turned-LN coined “Return by Death” specifically and made the death-and-rewind a thematic engine: every reset means a real death and accumulating trauma.
03
In KonoSuba: God’s Blessing on This Wonderful World!, NEET protagonist Kazuma Sato dies and is offered a wish by an obnoxious goddess. He chooses, out of pure spite, to take her with him to the fantasy world. She becomes the party’s perpetually-dunked-on, Drain-Touch-fearing water-and-resurrection priestess. Name her.
✓ Correct! Aqua. The goddess of water, useless and proud of it. Kazuma’s entire character arc is being saddled with three of the most dysfunctional party members in any RPG — Aqua (the goddess), Megumin (the explosion-only Crimson Demon mage) and Darkness (the masochistic crusader who can’t hit anything). Aqua’s mortal terror of Drain Touch and undead is one of the show’s longest-running gags.
✗ Wrong. The answer is Aqua. Megumin is the explosion-magic mage. Darkness is the masochistic crusader. Wiz is the lich shopkeeper. The goddess Kazuma drags into the fantasy world — and the source of about 90% of the party’s problems — is Aqua.
04
In That Time I Got Reincarnated as a Slime, Mikami Satoru is stabbed in modern Tokyo and reincarnates in a fantasy world as a low-tier blue slime monster — only to discover his new body has the absurd Predator Skill that lets him absorb anything he eats. He soon names himself after a great storm dragon he befriends in a cave. What name does he take?
✓ Correct! Rimuru Tempest — surname taken from Veldora Tempest, the Storm Dragon Rimuru befriends and absorbs in his first cave. By the time the series gets going, Rimuru is the founder and ruler of the monster nation Tempest, a Demon Lord, and the most powerful single character in his world. Fuse’s web novel started in 2013, Kawakami’s manga adaptation is over 25 volumes deep, and the 8-bit Studio anime is still ongoing.
✗ Wrong. The answer is Rimuru Tempest. Lugh Veleno is the protagonist of The World’s Finest Assassin Gets Reincarnated. Hajime Nagumo is the lead of Arifureta. Naofumi Iwatani is the Shield Hero. The slime who eats Veldora and names himself Tempest is Rimuru.
05
In Overlord (2015–), the Yggdrasil MMORPG’s servers shut down on the player Momonga, but instead of logging him out, he and his Great Tomb of Nazarick are pulled into a parallel world. He renames himself after his old guild — the same name that gives the show its menacing brand-villain register. What does he rename himself?
✓ Correct! Ainz Ooal Gown. Originally the name of Momonga’s 41-member Yggdrasil guild — the “Nine’s Own Goal” in original Japanese — he reclaims it as his personal alias to honour his absent guildmates. Maruyama’s LNs and Madhouse’s anime treat the protagonist as a slow-burn villain: a skeletal Eldritch Lord trying to figure out what he’s become while his floor guardians worship him as a god.
✗ Wrong. The answer is Ainz Ooal Gown. Albedo and Cocytus are NPC floor guardians of Nazarick. Demiurge is another floor guardian. Touch Me was a famous member of the original guild but isn’t Momonga’s alias. The protagonist takes the guild’s own name, Ainz Ooal Gown.
06
Sword Art Online’s first-arc death game traps Kirito and 10,000 players inside a 100-floor floating-castle MMO — if you die in the game, you die in real life. Each floor is a distinct biome and boss fight, and the only way out is to clear all 100. What is this castle/MMO called?
✓ Correct! Aincrad — the floating fortress designed by lead-developer-villain Akihiko Kayaba. Reki Kawahara’s LN began as a 2002 web novel and was adapted by A-1 Pictures in 2012, kicking off the modern isekai boom. The series moved through other servers/worlds across its sequels (Alfheim Online, Gun Gale Online, Project Alicization’s Underworld) but Aincrad remains the foundational setting and the brand image of the franchise.
✗ Wrong. The answer is Aincrad. Alfheim is the fairy-themed VRMMO of Season 1’s back half. Gun Gale Online is the FPS arc. The Underworld is the simulated world of the Alicization arc. The first-season death game is the floating fortress Aincrad.
07
Mushoku Tensei: Jobless Reincarnation (2021–) is widely cited as the foundational modern isekai web novel — published online from 2012, it’s often credited with defining the genre’s template. Its protagonist is a 34-year-old NEET reincarnated as a baby in a fantasy world, retaining his adult mind. What’s his new-life name?
✓ Correct! Rudeus Greyrat — born to swordsman father Paul and maid mother Zenith in the Buena Village in the Asura Kingdom. Rifujin na Magonote’s web novel ran from 2012–15 on Shōsetsuka ni Narō and is widely credited as the prototype for the modern reincarnation-isekai template. Studio Bind’s anime adaptation (2021–) is one of the genre’s most lavishly produced.
✗ Wrong. The answer is Rudeus Greyrat. Cid Kagenou is the lead of The Eminence in Shadow. Ars Lalatoya is Rudeus’s son later in the series, not Rudeus himself. Subaru Natsuki is the protagonist of Re:Zero. Rudeus is the reborn-as-a-baby protagonist of Mushoku Tensei.
08
A huge proportion of modern isekai (Re:Zero, Mushoku Tensei, Overlord, Slime, KonoSuba and many others) started as free amateur web serials hosted on a single Japanese user-generated-novel website — effectively the AO3 of the isekai boom — before being picked up by light-novel publishers. Name the platform.
✓ Correct! Shōsetsuka ni Narō (literally “Let’s Become a Novelist”), commonly abbreviated to “Narou.” Launched in 2004, by the early 2010s it had become the dominant funnel for amateur isekai web novels — with publishers like Kadokawa and Shueisha trawling its leaderboards for hits to acquire. So many isekai LNs originated there that “Narou-kei” (Narou-style) became a publishing-industry shorthand for the genre’s tropes (overpowered protagonist, cheat skill, harem dynamics, RPG status screens).
✗ Wrong. The answer is Shōsetsuka ni Narō (Narou). Comico is a Korean-style webtoons platform. Pixiv Novels is a sister site to the Pixiv illustration platform but isn’t the dominant isekai pipeline. Niconico Books doesn’t exist as a major publishing platform. Narou is where the modern isekai boom was incubated.
Status Window · Final Tally Your Isekai Standing
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Demon Lord-tier — or just a Truck-kun victim?
Sonic X probably isn’t a perfect alternative to playing the games, but between how well it adapts them, how seamlessly original characters and narratives are blended into the plot, and the surprising amount of depth given to the Sonic cast, it’s still worth watching, even after so many years. The anime is a truly underrated part of the Sonic the Hedgehog franchise, but fortunately, that doesn’t make it any less fun to watch.
The Vision Of Escaflowne
The Vision of Escaflowne’s main characters stand next to Earth, the moon, and a mecha
Shoji Kawamori is famous for his work on Macross and Transformers, but a work of his that’s equally deserving of attention is Sunrise’s The Vision of Escaflowne. In a rarity for isekai anime, Escaflowne incorporates both sci-fi and fantasy elements into its story, and the result is an incredibly deep and action-packed narrative that does wonders to sell the romance of the two leads, Hitomi and Van.
Considering all the amazing 90s anime a person can watch, it makes sense for The Vision of Escaflowne to have gotten lost in the shuffle, but with how much of a visual and narrative marvel the series is, it still holds up amazingly well. To this day, The Vision of Escaflowne is one of the most unique anime to watch in and out of isekai, and anyone who hasn’t already watched it would be remiss to pass it up.
Tsubasa: Reservoir Chronicle
Tsubasa-Reservoir-Chronicle-Cast
Japanese super group Clamp has one of the most extensive libraries in anime, and it all came together in Bee Train’s Tsubasa: Reservoir Chronicles. The series reworks Clamp’s entire library into a singular multiverse of sorts, and in doing so, it creates an incredibly enriching adventure story with amazing action and plot twists, and it still has all the same charm that’s commonly associated with them, as well.
As a love letter to their entire career, someone unfamiliar with Clamp’s work will miss much of the context for Tsubasa: Reservoir Chronicle, but even without all the references, it’s easy enough to follow the story. Doing so introduces someone to one of the most fun takes on an isekai story filled with plenty of action and romance, and 20 years later, it’s still an absolute gem of an anime.
Magic Knight Rayearth
Magic-Knight-Rayearth-Main-Cast-Visual
Tsubasa: Reservoir Chronicle proved that Clamp were the masters of isekai, but their first big foray into the genre was TMS Entertainment’s Magic Knight Rayearth. Unlike Tsubasa, Rayearth’s story is framed more around a traditional isekai narrative, but it stands out amazingly well for its blending of mecha and magical girl themes, all with an incredibly likable cast to tell the story with.
As big as isekai anime have gotten, plenty of them are still prone to fall under the radar, even though a few of them are nothing short of perfection.
Clamp has always found success in every anime genre they’ve tackled, and with how much of an endearing classic Magic Knight Rayearth is, it’s clear that they’ve even mastered isekai. Rayearth’s age has caused it to fall off in relevancy, but with Magic Knight Rayearth’s reboot coming in October, there’s plenty of room for it to have a revival.
Fushigi Yugi
Fushigi-Yugi-Key-Visual
Isekai and harem anime often go hand in hand, and one of the forerunners of that idea is Studio Pierrot’s Fushigi Yugi. From start to finish, there’s plenty of fun to be had seeing Miaka deal with her growing harem of boys while working through her duties as a priestess, and fortunately, those lighthearted moments never overshadow the surprisingly dark fantasy story at play from day one.
With its inconsistent visuals and some repetitive storytelling, it makes sense that Fushigi Yugi would have fallen off in popularity, but even after 30 years, the series is easily one of the most well-developed and generally fun takes on the isekai genre around. Series creator Yuu Watase is a major name in the world of shojo anime, and it’s safe to say that Fushigi Yugi is nothing if not her magnum opus.
The Familiar Of Zero
Familiar-Of-Zero-Cast
When it comes to classic isekai stories, none is more important than J.C.Staff’s The Familiar of Zero. Not only is it one of the oldest and most popular examples of a story about a loser getting sent to a fantasy world and acquiring magic powers and a harem of girls, but the authors of more modern works like Re:Zero and Mushoku Tensei have all cited The Familiar of Zero as an influence on their work, so without it, it’s safe to say that the modern isekai wouldn’t exist.
The Familiar of Zero, essentially being the godfather of modern isekai, does mean it can come off as a tad cliché, but even then, the depth of its worldbuilding, combined with its fun action and the great chemistry of its cast, still make it a fun anime to watch from start to finish. In many ways, The Familiar of Zero is even better than the shows it inspired, and that easily makes it the best classic isekai anime no one talks about.
Release Date
2006 – 2006-00-00
Network
AT-X, Chiba TV
Directors
Koji Kobayashi, Jiro Fujimoto, Yuta Maruyama, Tomio Yamauchi