In a landmark decision that has sent shockwaves through the anime community, Japan has officially declared the best isekai anime of all time through a comprehensive ranking by ABEMA, one of the country’s leading streaming platforms. The results, revealed during “Good Isekai Day” on November 12th, have crowned That Time I Got Reincarnated as a Slime as the undisputed champion of the isekai genre, beating out heavyweights like Overlord, Re:Zero, and Sword Art Online.
This official ranking isn’t just another popularity poll—it’s based on cumulative viewership data from millions of Japanese anime fans, making it the most definitive assessment of which isekai series truly resonates with audiences in the genre’s home country. The results offer fascinating insights into Japanese viewer preferences and what makes an isekai anime truly exceptional in the eyes of its most critical audience.
The Official ABEMA Ranking: Japan’s Top 9 Isekai Anime
ABEMA’s “Isekai Anime Grand Finale Ranking” was compiled by calculating the total viewership numbers across all isekai series available on the platform, creating a data-driven hierarchy that reflects genuine audience engagement rather than subjective opinions. The results reveal some surprising placements and confirm the status of long-running fan favorites.
1. That Time I Got Reincarnated as a Slime
2. Overlord
3. The Eminence in Shadow
4. Mushoku Tensei: Jobless Reincarnation
5. Is It Wrong To Try To Pick Up Girls In a Dungeon?
6. Re:Zero — Starting Life in Another World
7. KonoSuba: God’s Blessings On This Wonderful World
8. The Rising of the Shield Hero
9. Sword Art Online
What makes this ranking particularly significant is its methodology. Unlike many anime polls that rely on small sample sizes or vocal fan communities, ABEMA’s ranking reflects the actual viewing habits of millions of Japanese anime fans over an extended period. This gives it unprecedented authority in determining which isekai series truly capture the Japanese audience’s imagination.
Why That Time I Got Reincarnated as a Slime Reigns Supreme?
The question on everyone’s mind is: what makes Tensura (as fans affectionately call it) stand out in such a crowded genre? After analyzing the series and consulting with anime experts, several key factors emerge that explain its dominance in the Japanese market.
The Perfect Balance of Escapism and Substance
That Time I Got Reincarnated as a Slime succeeds where many other isekai series fall short by delivering the ultimate fantasy fulfillment while maintaining narrative depth. The series follows Satoru Mikami, a 37-year-old office worker who dies and is reincarnated as a slime monster in a fantasy world. This premise might sound simple, but the execution is masterful.
What sets Tensura apart is its understanding of what Japanese audiences crave in their escapism. Unlike darker isekai like The Rising of the Shield Hero, which can feel overly grim, or purely comedic series like KonoSuba, which sometimes lack substance, Tensura strikes the perfect balance. It offers the wish-fulfillment fantasy of becoming powerful and important in a new world while simultaneously delivering meaningful character development, political intrigue, and emotional stakes.
Masterful Tone Balancing: From Comedy to Tragedy
One of Tensura’s greatest strengths is its ability to seamlessly shift between different narrative tones. The series can deliver laugh-out-loud comedy in one episode—like the infamous “Hey! Butts!” episode—then pivot to heart-wrenching tragedy and high-stakes conflict in the next. This tonal versatility keeps viewers engaged and prevents the series from becoming predictable or one-dimensional.
For example, the series handles Shizue Izawa’s struggle with the Ifrit spirit with genuine emotional weight, making her story arc profoundly moving. Yet it also features Gabiru’s comically over-the-top antics that provide much-needed levity. This balance ensures that Tensura appeals to a broad audience spectrum, from those seeking light entertainment to viewers craving more substantial storytelling.
Exceptional World-Building and Political Depth
Unlike many isekai that focus primarily on combat and power progression, Tensura invests heavily in world-building and political maneuvering. Rimuru’s journey from a simple slime to the leader of a nation involves diplomacy, alliance-building, and governance—elements that resonate strongly with Japanese audiences who appreciate complexity in their fantasy narratives.
The series doesn’t just present a fantasy world; it shows how that world works, with detailed economic systems, political relationships between different races and nations, and the consequences of Rimuru’s decisions as a leader. This depth adds layers of rewatch value and intellectual engagement that many other isekai series lack.
A Cast for Every Viewer: Character Design Excellence
Tensura boasts one of the most diverse and well-designed supporting casts in isekai anime. From the dragon Veldora to the ogre Shion, the demon lord Milim to the dwarf Kaijin, the series offers characters with distinct personalities, designs, and character arcs that ensure every viewer can find someone to connect with.
This character variety isn’t just cosmetic—each character serves a narrative purpose and undergoes meaningful development throughout the series. Rimuru himself, despite becoming incredibly powerful, maintains relatable flaws and continues to grow as a character, preventing him from becoming the boring, overpowered protagonist that plagues many isekai series.
The Surprising Contenders: Analysis of the Top 9
While Tensura’s victory might not shock seasoned anime fans, several placements in ABEMA’s ranking reveal interesting trends in Japanese viewer preferences.
Overlord’s Strong Second Place
Overlord securing the #2 spot demonstrates Japanese audiences’ appreciation for darker, more complex isekai narratives. The series, which follows the undead overlord Ainz Ooal Gown as he navigates a world that has suddenly become real, offers a fascinating exploration of power, morality, and identity.
What makes Overlord’s placement particularly interesting is how it contrasts with Tensura. While Tensura represents optimistic nation-building, Overlord presents a more cynical view of power and leadership. The fact that both series rank so highly suggests Japanese isekai fans appreciate both approaches to the genre.
The Eminence in Shadow’s Breakout Success
At #3, The Eminence in Shadow represents a newer take on the isekai formula that has resonated strongly with Japanese audiences. The series, which follows a boy who reincarnates into a fantasy world and pretends to be a mastermind controlling a secret organization, brilliantly parodies isekai tropes while delivering genuine entertainment.
Its high placement indicates that Japanese viewers appreciate isekai that can be self-aware and humorous while still providing engaging fantasy content. The series’ success also suggests that the isekai genre continues to evolve and find new ways to captivate audiences.
The DanMachi Controversy
Perhaps the most controversial placement is Is It Wrong To Try To Pick Up Girls In a Dungeon? at #5, as many anime purists argue it’s not technically an isekai series. While it features fantasy elements and dungeon crawling, the protagonist Bell Cranel wasn’t reincarnated or transported from another world—he’s a native of the fantasy world.
This inclusion suggests that ABEMA’s ranking may have used a broader definition of “isekai” that includes fantasy series with similar themes and appeal, even if they don’t strictly follow the “transported to another world” premise. It also indicates that Japanese viewers may care less about genre technicalities and more about overall entertainment value.
What This Ranking Reveals About Japanese Anime Preferences?
The ABEMA ranking offers valuable insights into what Japanese audiences value in their isekai anime, revealing several key trends that differ from Western preferences.
The Importance of Optimism and Hope
Unlike Western audiences who often gravitate toward darker, grittier narratives, Japanese viewers clearly favor isekai series with optimistic tones and hopeful messages. Tensura’s emphasis on cooperation, nation-building, and creating a better world resonates more strongly than series focusing solely on survival or conflict.
This preference for optimism extends beyond just Tensura—high-ranking series like Overlord and Mushoku Tensei, despite their darker elements, ultimately focus on growth, achievement, and positive change rather than despair or nihilism.
World-Building Over Pure Action
Japanese audiences demonstrate a clear preference for isekai with detailed world-building and systemic depth over series that focus primarily on combat and power progression. This explains why series like Tensura and Overlord, which invest heavily in their worlds’ economies, politics, and cultures, rank higher than more action-focused isekai.
This appreciation for world-building suggests that Japanese viewers engage with isekai not just as power fantasies but as immersive experiences that allow them to explore fully realized fantasy worlds.
Character Development Matters
The ranking clearly shows that Japanese audiences value character development and emotional depth. Series that take the time to develop their characters and explore their motivations consistently rank higher than those with more superficial characterizations.
This explains why Mushoku Tensei, despite its controversial elements, ranks so highly—its protagonist undergoes genuine character growth and development throughout the series, making his journey compelling and emotionally resonant.
The Cultural Significance of “Good Isekai Day”
ABEMA’s decision to declare November 12th as “Good Isekai Day” and release this ranking speaks to the genre’s cultural importance in Japan. Isekai has evolved from a niche subgenre to one of anime’s most dominant categories, influencing everything from light novel publishing to video game design.
The celebration of “Good Isekai Day” with free streaming marathons of the top-ranked series demonstrates how the genre has become a cultural touchstone, bringing together millions of Japanese viewers to celebrate their favorite fantasy worlds and characters.
What This Means for the Future of Isekai Anime?
The ABEMA ranking isn’t just a retrospective look at what’s been popular—it’s a roadmap for where the isekai genre might be heading. The success of series like Tensura and The Eminence in Shadow suggests that future isekai will need to balance traditional elements with fresh perspectives to capture Japanese audiences’ attention.
We’re likely to see more isekai that:
- Balance multiple narrative tones effectively
- Invest in detailed world-building and political systems
- Feature diverse, well-developed supporting casts
- Offer both escapism and substantive storytelling
- Find new ways to innovate within the genre’s conventions
Conclusion: A New Standard for Isekai Excellence
Japan has officially spoken, and the message is clear: That Time I Got Reincarnated as a Slime represents the pinnacle of what the isekai genre can achieve. Through its masterful balance of escapism and substance, exceptional world-building, and diverse cast of characters, Tensura has set a new standard for excellence in isekai anime.
This official ranking by ABEMA provides invaluable insights into Japanese viewer preferences and what makes an isekai series truly resonate with its home audience. As the genre continues to evolve and expand, the lessons from Tensura’s success will undoubtedly influence future isekai productions for years to come.
For anime fans worldwide, this ranking serves as both a celebration of isekai’s achievements and a guide to the genre’s finest offerings. Whether you’re a longtime isekai enthusiast or new to the genre, the series in ABEMA’s top 9 represent the best that Japanese anime has to offer in the realm of fantastical otherworld adventures.