Anime might not typically be known for purely science fiction fare, but there have nonetheless been a number of great sci-fi entries in the medium in past decades. Some of these shows are surefire classics, while others are better left off forgotten. There are a few science fiction anime titles, however, that both stand the test of time yet have failed to catch on.

These anime series are great examples of their particular science fiction subgenres, but for one reason or another, did not achieve mainstream success. These range from dark and gritty cyberpunk thrillers and 1950s throwbacks to apparent Pokémon ripoffs that are far more than the sum of their parts. Here's a look at some of the best sci-fi anime from 11 to 20 years ago that you might not remember.

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Ergo Proxy

Re-l Mayer and Iggy standing side by side in Ergo Proxy

Ergo Proxy was released in 2006 and involved creators who worked on the likes of Cowboy Bebop and Ghost In the Shell. When a virus affects the many androids of its world, they rise up with newly developed sentience. Inspector Re-L Meyer looks into the situation, but in doing so, discovers the existence of another species created by the government.

Fans of the aforementioned Ghost In the Shell, as well as Blade Runner and other works tackling human/robot relationships, will love Ergo Proxy, as will fans of neo-noir and psychological mysteries. Mysticism and Gnosticism are also big elements throughout the story, so its occasionally hard-to-parse symbolism may require not one, but two viewings just to take everything in.

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Blue Gender

Attack blue gender horror anime

Blue Gender, made by the creator of both Votoms and Gasaraki, combines elements of mecha and giant robot anime, gruesome body horror and post-apocalyptic science fiction. It skirts the rules somewhat on this list, coming out in 1999 but finishing airing in 2000. The protagonist is Yuki Kaido, who is put into cryogenic stasis after being diagnosed with a rare disease. He awakens decades later to find the Earth embroiled in a battle with bug-like monsters. He discovers that he's one of several "sleepers" reawakened by the human citizens of the Second Earth colony. While trying to survive amid countless deaths, Yuki and a woman named Marlene discover the truth behind the bugs and the sleepers.

Anyone who's a fan of post-apocalyptic stories against inhuman foes like Attack on Titan will love Blue Gender. It also shares some superficial similarities to science fiction classics like Starship Troopers, recent anime like Knights of Sidonia and even the controversial Terra Formars, making it a great show for those wanting to see humanity struggle for survival in a dark future.

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Texhnolyze

Ran holding a flower in Texhnolyze with the anime title card

Texhnolyze is a cyberpunk thriller from 2003 that focuses on Ichise, a prize fighter who lives in the futuristic city of Lux. This broken-down dystopia was a once prosperous metropolis that's since fallen into disarray, with its confined society doing the same. Many of its citizens, including Ichise, use Texhnolyze -- advanced prosthetics that make up for the limbs that were taken from them, often through extremely violent means.

Ichise finds himself working for the powers that be in Lux until a clairvoyant girl named Ran teams up with him to save the city from total collapse. The show is a must-watch for fans of cyberpunk, including recent shows like the cyberpunk boxing series Megalo Box, as well as those who like both psychological and supernatural thrillers.

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Project Blue Earth SOS

The very much forgotten Project Blue Earth SOS involves the seeming disappearances of trains after they are hit by a mysterious rainbow light. This is investigated by two boys named Billy and Penny, who realize that aliens are behind the affairs. The military then sends forth its Sky Night aircraft in order to defend the planet against the harrowing alien threat.

The series is set in an alternate retro-style version of the 1990s, though it's actually based on a book written a few years after World War II. This retro 1950s style matches up with the animation, art designs and even some of the posters, which evoke classic Toho sci-fi movies. Fans of '50s invasion flicks and sci-fi classics will definitely get a kick out of this well-received but not often remembered title.

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Angelic Layer

Angelic Layer Pokemon Rip Off

Coming out in the early 2000s, Angelic Layer adapted a CLAMP manga that was still running just as the show finished airing. The series is about a young girl named Misaki Suzuhara who becomes obsessed with the hit game Angelic Layer, which involves battles between mentally controlled robotic dolls. As the plot unfolds, Misaki learns more about herself and the origins behind the popular game.

Seen by some as CLAMP's take on the growing popularity of PokémonAngelic Layer has a lot more plot development and depth than its video game tie-in competitor. The series has a very classic art style and design aesthetic typified by previous anime in the mid and late '90s, and it also stands out among Pokémon derivatives for having a young girl as the protagonist. Featuring notable cameos from other CLAMP characters, the show is a cute classic that's perfect for CLAMP fans and anyone wanting to see tiny dolls duke it out.

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