Japan, present day: Alien Invaders are everywhere, taking over peoples' bodies. Fighting them is Isuzu Ayane, an introverted young girl with the ability to control powerful dimensional Gates. Under the guidance of Kageyama Reiji, a mysterious businessman, she battles Invaders and recruits new Gate Keepers. Will she and her new comrades be able to save the earth?
At a typical elementary school in Japan, yearly chores are being distributed. Yuri and 3 other students are chosen to be the beneficiaries of the alien hats for the year. Alien hats?! Yuri's sentiments, exactly. Despite her misgivings, she and her classmates must round up stray aliens that have escaped from a crashed spaceship -- with the help of the alien hats, of course.
Do you like young girls battling endless waves of weird-looking aliens? Do you care if one of the main characters is a bit whiny and hates her job as alien hunter? Then these animes are for you. While the animes differ in how the girls' powers are obtained, they still share the motif of child soldiers.
While transporting bio-weapon lifeforms, Agent DD, member of an alien police force, is forced to crash land on Earth. Amidst the chaos of the crash, a bio-weapon escapes and DD is forced to fight it, while accidentally activating a Liberus, a liquid battle suit. Tsubasa, a shy girl, unwillingly comes into contact with the Liberius and is thereafter forced to fight for the survival of Earth.
One night, Madoka has a terrible nightmare – against the backdrop of a desolate landscape, she watches a magical girl battle a terrifying creature, and lose. The next day, the teen's dream becomes reality when the girl – Homura – arrives at Mitakihara Middle School as a transfer student, mysteriously warning Madoka to stay just the way she is. But when she and her best friend Miki are pulled into a twisted illusion world and meet a magical creature named Kyubey, the pair discovers that magical girls are real, and what's more, they can choose to become one. All they must do is sign a contract with Kyubey and agree to fight witches that spread despair to the human world, and in return they will be granted a single wish. However, as Homura's omen suggests, there's far more to becoming a magical girl than Madoka and Miki realize...
Both of these animes involve young girls fighting against monsters that are not all they seem. While Gatekeepers also has male magic users, both of these animes seem to take the Magical Girl genre and shake it up. The character types are also very similar (whiny one, fighting one, emotionally challenged one... etc). Also, aliens.
Ayato Kamina may seem like an average boy in a devastated world, but after being captured by TERRA, a military organization set on saving the world from the Mu, an alien race set on "tuning" the world, he realizes he is an instrument in deciding the fate of humanity and piloting RahXephon. Not only is Ayato the only person who can control the mecha, but he also has a terrible fate of his own. Holding onto memories of his old life and grasping to keep his own humanity, he must struggle in this new world and realize his true potential with RahXephon.
Some years into the future, a strange, unexplainable natural disaster has broken off a piece of the Japanese mainland. Known as the Lost Ground, it is now inhabited by people with Alters -- machine-like extensions of their own will. In order to keep the peace on the Lost Ground, the HOLY organization uses its own Alter capabilists to police the region. In the midst of the chaos is a young man named Kazuma, whose life will soon change forever as he discovers his hidden abilities, and how to wield them.