When it comes to anime, there are countless mainstream hits and historically important series. But what anime connoisseurs really love and seek out are the anime that are so bad that they become impossible to forget.

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Whether it's because of shoddy production or controversial content, these so-bad-they're-good anime were forever immortalized in the anime community. Make no mistake, these anime are all acquired tastes and no one is under any obligation to watch them right away.

CONTENT WARNING: Some sensitive plots and themes will be mentioned here. 

10 Mars Of Destruction Is The Epitome Of Laziness

The AAST agents take on the Ancients in Mars of Destruction

Mars Of Destruction is a visual novel about an alien invasion in Tokyo. The plot itself isn't anything noteworthy, but its official animation is one of the most legendarily bad anime ever made. Even worse (or better) is that it's basically a bootlegged Neon Genesis Evangelion (which recently ended), from its dream sequences to its aliens' origins.

Despite barely clocking in at 20 minutes, this one-shot OVA had so little effort put into it that its animation, writing, voice acting, and even the sound design were all amateurish at best. The only thing that could make Mars Of Destruction even better is an intentionally awkward English redo, which it got, courtesy of Super BWB's fandub.

9 Mad Bull 34 Is The Craziest Police Anime Ever Made

The 34th Precinct Cops In Mad Bull 34

As a buddy-cop series, Mad Bull 34 doesn't really stand out. What makes it memorable is how excessive it got, especially in terms of violence and profanity. All of this is thanks to John "Sleepy" Estes, the titular Mad Bull who's also the living combination of overcompensation, brash American stereotypes, and a childish interpretation of what cops do.

Besides Sleepy's ridiculous manliness and very unique grenade belt, Mad Bull 34 is best remembered for its wanton violence and excessively sexually charged scenarios. Mad Bull 34 wouldn't feel out of place when put beside any of the equally sleazy and politically incorrect cop movies of the '80s, and that's why it still has a dedicated fanbase even today.

8 Angel Cop Is So Unbelievably Offensive It Becomes Hilarious In Hindsight

Angel Aims Her Gun In Angel Cop

On paper, Angel Cop looks like nothing more than another cyberpunk OVA not unlike Ghost In The Shell. Beneath its familiar trappings, though, is a plot so wrongheaded that it would offend anyone. In brief, Angel Mikawa is a violent cop who has to stop a conspiracy from undermining the immoveable superpower that is Japan.

Coupled with questionable politics and excessive patriotism are oddly well-animated displays of ultraviolence and an English dub that reveled in the chance to be as profane as possible. Angel Cop's ironic appeal comes from its audacity to even exist, and it's a classic guilty pleasure that the morbidly curious should seek out.

7 MD Geist Is Juvenile & Nihilistic Beyond Belief

Geist Stands Firm In MD Geist

The two-part OVA MD Geist is the kind of post-apocalyptic anime that, conceptually, shouldn't stand out. It follows the titular super-soldier as he wreaks havoc on the Earth's Mad Max-inspired wastelands. What made this title immortal, though, was its execution, which went above and beyond to be as bloody and nihilistic as possible.

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Geist's warpath is (in)famous for its intense brutality and needlessly operatic tone, which is best summarized by the bombastic theme song "Violence Of The Flame" and its sloppy English dub. MD Geist is a juvenile post-apocalyptic trek where everything is solved with violence, and there's no better time capsule of anime's awkward phase from the late '80s to the '90s than this.

6 Future Diary Is The Original Edgy Death Game

The Diary Holders In Future Diary

As the death game anime that started it all, Future Diary is wrought with many of the subgenre's usual flaws. Examples include: an ineffectual yet implausibly overpowered protagonist, a yandere love interest who's inexplicably obsessed with the hero, an immaturely nihilistic worldview, a romantic subplot that feels out of place, and more.

Normally, such faults would be detrimental to a death game anime. But since Future Diary is arguably the first of its kind, not only does it get a pass but it gets credit for creating and popularizing these tropes in the first place. Future Diary has all the hallmarks of a boilerplate edgy power fantasy, and it's all the more entertainingly bad for it.

5 Cross Ange Is A Wild Ride That Had No Concept Of Restraint

Princess Angelise In Cross Ange

Simply put, Cross Ange is what would happen if the mecha anime were mixed with a sleazy women-in-prison sexploitation movie from the '70s. Despite the gratuitous amount of fanservice, Angelise's struggles still dared to tackle heavy themes such as class oppression, racism, war crimes, cosmic existentialism, and more.

What made the anime another kind of special was its troubled production, resulting in many instances of recycled footage and off-model characters. Because of these and every episode's habit of one-upping the previous one in the most unapologetic ways, Cross Ange became an ironic hit among even the most experienced mecha fans.

4 Yu-Gi-Oh! The Movie: Pyramid Of Light Is A Feature-Length Ad For Trading Cards

Yami Plays A Duel In Yu-Gi-Oh The Movie The Pyramid Of Light

Despite tons of quotable moments, a surprisingly heartfelt ending, and the abridged series’ existence, the main Yu-Gi-Oh! Duel Monsters anime (4Kids dub or otherwise) is a lot more boring than people actually remember. Its official movie, on the other hand, is a succinct goldmine of everything hilariously wrong about Yu-Gi-Oh!

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Pyramid Of Light is one of the most transparent cash-grab anime ever made, and it shows. The only reason Anubis and Yami summon incredible monsters is to advertise their cards, and the movie's duels are filled with Deus Ex Machinas for the sake of looking cool. Not only did the plot barely makes sense, but the overdramatic English dub made an already hilarious experience even funnier.

3 Garzey's Wing Is The Holy Grail Of Classic B-Grade Anime

Christopher Senshu in Garzey's Wing.

On its own, Garzey's Wing is already something to behold. It's a three-part OVA that tells a confusing isekai story, that just so happens to have been made by JC Staff and Mobile Suit Gundam mastermind Yoshiyuki Tomino. But when the English dub by Central Park Media is taken into account, it becomes legendary.

Garzey's Wing has one of the most memorably bad English dubs ever recorded, so much so that it's become the anime fandom's answer to The Room. Just like Tommy Wiseau's classic B-movie, Christopher Senshu's fantasy adventure in Byston Well was a midnight screening hit and right of passage among anime veterans.

2 Sword Art Online Is Still The Self-Indulgent Isekai Power Fantasy To Beat

Kirito Holds Asuna In Sword Art Online

To put it bluntly, Sword Art Online is a transparent self-insert power fantasy that's directly responsible for the polarizing gaming isekai boom of the 2010s. Kirito barely has any challenges or flaws, and is the equivalent of an anime protagonist with gaming cheats activated. It's also for these reasons that the anime is a modern so-bad-it's-good hit.

In its effort to please fans with blatant wish-fulfillment, Sword Art Online (especially the original storyline) breaks its own tension and internal logic to make Kirito win in the most hilariously egregious ways. Highlights include hacking the source code to undo a tragic death and being a ridiculously overpowered "Beater."

1 Ghost Stories' English Dub Is A Legend In The Anime World

Satsuki and friends in Ghost Stories.

The original Ghost Stories isn't anything spectacular; it's a glacially paced supernatural thriller starring precocious kids that bombed when it aired in Japan. Ghost Stories' English dub from ADV Films, on the other hand, is a legend in the anime fandom. Basically, the dub is the anime equivalent to Mystery Science Theater 3000. 

While they had to keep the basic plot and characters' names, ADV Films was given carte blanche over the dub. The result was one of the most irreverent localizations of all time, which elevated a bland anime to so-bad-it's-great territory. While not all of the jokes aged perfectly, the fact that this dub even exists is a hilarious miracle on its own.

NEXT: 10 Abridged Series More Popular Than The Actual Anime