Isekai is a surprisingly lighthearted genre, considering its subject matter features the dark nature of its characters being put into another world. However, the ongoing gag of "truck-kun" perfectly demonstrates how happy-go-lucky isekai's community has become. Instead of viewing death as some sad experience, isekai views it optimistically as the start of a new life and an exciting adventure.

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Still, not all isekai series follow that same positive direction. Some shows make it a point to highlight the darker undertones of what being sent to another world actually means. Despite the very optimistic and even humorous atmosphere of some series, there are others where everything doesn't go well for the hero, and things end badly.

Updated by Sage Ashford on February 28, 2023: Most isekai tend to embrace the power fantasy element to such an extent that very little dark ever happens. However, there are others that aren't afraid to go down a dark path just to offer some variety for the viewers. We've added a few more isekai anime with surprisingly sad endings that fans can try out.

15 No Game No Life Zero

Riku and Shuvi in No Game No Life Zero.

The No Game No Life television series is light-hearted and comedic, focused on a brother/sister pair who are unbeatable when it comes to any kind of games. When the two land in the world of Disboard, they decide to help the humans make their way to the top of all the races on the planet.

No Game No Life Zero goes down a completely different road, though. A prequel set in the distant past of Disboard, it shows how the world became one ruled entirely by games instead of traditional conflict. In this world, a pair of close friends, Riku and Shuvi, risk everything to try and stop the endless fighting on their planet. While they succeed, it ends up costing them their lives.

14 Fate/Grand Order - Absolute Demonic Front: Babylonia

Fate/Grand Order - Absolute Demonic Front: Babylonia image.

Fate/Grand Order - Absolute Demonic Front: Babylonia is an adaptation of the "Babylonia" chapter of the phone game. Near the end of their journey, protagonists Ritsuka Fujimaru and Mash Kyrielight travel to one of the earliest parts of human history, landing in 2655 B.C. Mesopotamia. There, they discover all of humanity has fallen to the dangers of three powerful goddesses except a single city: Uruk, where all of humanity has retreated.

Though in theory, Ritsuka and Mash are meant to protect humanity, what "protecting" really means is keeping the timestream working. In the end, though the two are successful at their goal, they utterly fail to protect Uruk and the people there. Though they "win," the last human city is left destroyed.

13 That Time I Got Reincarnated As A Slime

Characters from TenSura/That Time I Got Reincarnated As A Slime.

Though this isekai series mostly has positive endings, the ending to That Time I Got Reincarnated as a Slime Season 2 had some surprising gut punches. For one, though Clayman had been the primary antagonist for much of the series, his defeat is viewed through the eyes of his friends. The Moderate Harlequin Alliance is left realizing one of their closest allies has been dispatched by their enemies.

Distraught and frustrated, Laplace strikes out at one of the heroes' close allies, killing him out of frustration. Though this is a universe where things tend to go positively, the end of the series closes with viewers wondering what can be done about the remaining members of the Harlequin Alliance, who are all even more powerful than Clayman.

12 Aura Battler Dunbine

An image from Aura Battler Dunbine.

All the hero of Aura Battler Dunbine wants to do is return to his home. After being pulled to the fantastical world of Byston Well, Sho Zama is forced to fight, learning to pilot a giant robot known as Dunbine. The longer he fights, the more powerful he becomes, eventually becoming the strongest Aura Power wielder. However, having that much power isn't necessarily a good thing.

When Sho finally finds a way to return home, his family doesn't even think he's the real Sho, believing he passed away after he was sent to Byston Well. Even worse, though, actually ending the war costs Sho his own life and leads to the destruction of most of the forces on both sides of the Byston Well conflict.

11 Digimon Tamers

An image from the finale of Digimon Tamers.

Though Digimon Tamers spends much of its time in the Real World, going back and forth to the Digital World is still just as important as ever. Tamers has a different feel to it from other Digimon series, but in the end, it does all come down to a battle to protect both worlds from being destroyed. While they're successful in getting rid of the D-Reaper, it comes at a cost.

All the Digidestined are forced to give their Digimon up, as the Digimon are forced to return to the Digital World. It's a bittersweet moment for the heroes who managed to save the world, as they're separated from the friends that helped them grow into people who could help them save the world. The ending reveals Takato finding a portal to the Digital World, but there are still no promises that it'll work for everyone involved.

10 Magic Knight Rayearth

Princess Emeraude and Zagato hugging in Magic Knight Rayearth.

Magic Knight Rayearth is a bit deceiving: its subject matter consisting of magical girls and mecha robots in a fantasy world may lead fans to expect a more lighthearted series. However, the first season's ending and its implications for the second one lead Magic Knight down a dark path with tragic consequences.

While the show revolves around its three protagonists saving a damsel in distress from a usurper, this is only a surface-level truth. After killing the villain, they find that the princess they set out to save was so in love with him that his death drives her into the depths of grief — forcing the heroes to make a tragic decision.

9 Corpse Party: Tortured Souls

The students in Corpse Party: Tortured Souls conduct a ritual.

Corpse Party becomes a sad story long before its ending. When a group of students gets transported to a strange haunted school after performing a ritual, their fates are already sealed.

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Corpse Party is one of the scariest — and goriest — isekai, and its characters are constantly being haunted by their own classmates as each of them dies one by one. It's a grim tale that is ultimately destined for a tragic ending, as this is one isekai in which no one is getting reincarnated in the way they would have hoped.

8 Mushoku Tensei: Jobless Reincarnation

Rudeus gazes into the distance surrounded by snow in Mushoku Tensei.

Mushoku Tensai sometimes receives hate from viewers who see some of its subject matter as inappropriate. However, those same themes make the show realistic and unique enough to become one of the most popular new isekai series.

The end of Mushoku Tensai's Season 2 solidified its place as one of the more realistic and tragic isekai released in recent years. The show certainly has much more to say about Rudeus' story, but as it stands, its characters have found themselves in tragic circumstances.

7 I'm Standing On A Million Lives

Cover art for I'm Standing on a Million Lives.

I'm Standing On A Million Lives' protagonist is a conflicted, self-aware high schooler named Yusuke who struggles with life in both worlds he's forced to contend with. That backdrop leads him to conclude at the end of Season 1 that the world is wrong and he's the only right one.

However, in the second season, Yusuke seems to make new friends in the other world. He ultimately saves the day, and he and his party are sent back to reality. However, the sad truth is that this all had little effect on his perspective. When asked how he feels about things as the credits roll, he responds with, "I do still hate this city."

6 Cautious Hero: The Hero Is Overpowered But Overly Cautious

An image from Cautious Hero.

Cautious Hero consists of the quintessential generic isekai protagonist: Seiya is overpowered and quirky with a strong sense of justice. That's why his fate at the end of the series is so tragic that it takes fans by surprise.

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Despite Seiya's immense power, he can't seem to destroy the demon lord he was reincarnated to defeat. In the end, the only way to finish him off once and for all is for Seiya to use his most powerful ability, which will also inevitably take his own life. Seiya's tragic sacrifice is a sad moment, though the show gives some respite through the promise of his rebirth.

5 Sword Art Online

Kirito and Asuna holding hands in Sword Art Online.

Sword Art Online's first season has been marginally accepted by anime fans as its best and perhaps the most influential show in isekai to date. Part of the draw of the series was its high-stakes moments in which Kirito and Asuna faced certain death if they were destroyed in the virtual world of SAO.

That's part of what made the show's ending tragic: fans watched as both Asuna and Kirito were killed in battle. Though they were both revived in one of the greatest acts of plot armor ever, the feels weren't entirely over. When Kirito eventually found Asuna in the real world, she had still not woken up from the game. This set into motion Kirito's seemingly perpetual return to virtual game worlds.

4 Re:Creators

The many isekai'd characters assemble in Re:CREATORS

Re:Creators follows a young otaku who is surprised to find that the main character from his favorite anime has been transported into his world. This would all be well and good if it weren't for the fact that a terrifying villain was also sent to his world alongside her.

The sad fact about Re:Creators is that it all stems from the untimely death of the main antagonist's creator, who is seeking revenge on the world for causing her depression. The only way the heroes can stop Altair is to create an image for her Creator, Setsuna, which leads to a heart-wrenching moment in which fans can only feel sorry for the villain.

3 Angel Beats!

A scene from the Angel Beats! ending.

Angel Beats! already takes place in the Afterlife, so it shouldn't surprise fans that things may get dark. The show follows Otonashi, a boy who forgets his past life after being reborn after death. Because he can't recall the memories of his past, he is unable to move on to the next life after death and is stuck in a sort of limbo in the Afterlife.

Though Otonashi and his friends finally graduate and can move on, this is a bittersweet truth. As everyone moves on to the next plane of existence, things are particularly hard for Otonashi because this means that he has to leave behind the attachments he formed with his friends, especially with Angel.

2 Now And Then, Here And There

Shu and Lala Ru in a prison in Now and Then, Here and There.

Now And Then, Here And There is a cult classic anime about a boy named Shuu who sets out to rescue a mysterious girl only to be sent to a terrifying new world. This world is equal parts scary and tragic: a desert dystopia torn apart by war and famine.

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Now And Then is known for its moody atmosphere and emotional moments. Shuu undergoes terrible circumstances to rescue Lala-Ru, and the series' ending is made even more tragic by the things he has to go through to get there.

1 Spirited Away

Haku and Chihiro Ogino hugging in Spirited Away.

Studio Ghibli has frequently been referred to as the Disney of Japan. While the studio's success certainly warrants that comparison, there are differences between the two. While Disney will come with a preconception of uplifting children's stories, Studio Ghibli has often covered much darker themes than its American counterpart, and its immensely famous film Spirited Away is an example of that.

Spirited Away expresses the Disney/Ghibli dichotomy perfectly because Disney handled the film's American dub. In it, one change is made that makes the ending feel more complete and a little less sad: Chihiro remembers the events of the spirit world. In the Japanese version, she doesn't remember; she only feels within herself a change, which proves even sadder considering the strong bonds she left behind.

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