Hades Project Zeorymer

In the near future, a secret society, Nematoda, with ambitions of world domination, hired three men, Professor Akitsu, Professor Himuro, and Professor Wakatsuki, to build the ultimate "G-Class" giant robot, Zeorymer. Nearly two decades later, on his deathbed, Professor Akitsu tells his son, Masaki Akitsu, that Zeorymer must not awaken. A short time later, a new student transfers into Masaki's school, named Miku Himuro. She quickly persuades him to meet her adopted father, Professor Himuro, and Masaki is curious to find out what is going on, and what his father meant in his final words. Traveling by a high-speed pod hidden under the city, he meets Professor Himuro in a vast underground facility. Nematoda's General Golshid, aware of the Himuro's appearance in Japan, send a G-Class robot to assault their base and kill them, as they believed they had the only "Joint". Himuro compels Masaki to pilot Zeorymer and save them, as he is the only one that can pilot it. Once he agrees, Himuro and his daughter head to an operating room without Masato's knowledge, and he installs a sphere called a "Dimensional Joint" - a flawed duplicate of the original - into his daughter's womb, and she is teleported to within Zeorymer's "eye". This is necessary to utilise Zeorymer's true abilities - without them, it is simply an outdated G-Class robot. Though Masaki stumbles with the unfamiliar systems, Zeorymer eventually awakens fully, Masaki undergoes a strange and short-lived shift in personality, and with the spherical energy weapon on the back of Zeorymer's hand, destroys its opponent in a single attack.

Soon, Nematoda sends its three newest and most powerful robots after Zeorymer. Finding its pilots at school, they attempt to apprehend them, but Zeorymer is teleported to their location. Masaki's personality shifts again, and Zeorymer fights the three, despite being in the middle of a city, showing no care for civilian casualties. Zeorymer shows its power, being much faster than the fastest of the three, vastly stronger than the strongest of the three, and takes the many, many missiles of the third without damage. Finally, Zeorymer activates both of the spheres on the back of its hands and taps them together, the shockwave cleaving the final robot and several buildings behind it in two. As a result, the city has undergone immense damage, and many of its citizens are surely killed, including all of their schoolmates.

With Nematoda, General Golshid, seeing the vast power of Zeorymer, elects to pilot the powerful Rose C'est La Vie, a G-Class robot that had crippled test pilots, even at less than full power. Knowing he has little choice Golshid still elects to go, with Rose C'est La Vie at full power. Upon returning to base, Professor Himuro is shown to have collapsed and is dying of an incurable disease, and Masato realised the level of destruction fighting would cause, but strangely didn't care. Suddenly teleported to Zeorymer's cockpit, it's revealed that Masaki is the revived, evil, Professor Wakatsuki, reduced to an embryo and reborn to escape an inevitable death, Miku was Himuro's wife, who had been cheating on her husband with him, had undergone the same process as she had been caught in the same event, and that Himuro was the one to attempt to kill them. Though the three scientists were conspiring against Nematoda while they worked for the organisation, Wakatsuki was planning to betray the others and take Zeorymer for himself. Akitsu and Himuro had stolen the embryos to stop the revival, and Akitsu then took Masaki's embryo and fled from his other colleague as well. However, by activating Zeorymer, the memories and personality of Wakatsuki had been installed into Masaki, though the same was not true of Miku. Following this reveal, Wakatsuki forces himself on Miku, sexually, and uses sex to make her his.

Rose C'est La Vie lands and fights Zeorymer. Golshid successfully tears off one of Zeorymer's arms, but it is instantly regenerated in its entirety. He then successfully destroys its cockpit, killing Wakatsuki, to which both cockpit and pilot are regenerated completely. Defeated and nearly destroyed, Golshid is saved by the sudden loss of power of Zeorymer, as the Dimensional Joint had finally failed. With both robots retreating, Wakatsuki installs a new Dimensional Joint into Miku, and upon her awakening, suddenly shifts back to Masaki for a moment. With both Wakatsuki and Miku realising, Wakatsuki reinforces himself and flees. In the midst of coitus with Miku, Masaki comes to the realisation that the "fake Masaki Akitsu" was not a fake - it was not Wakatsuki's personality that was installed, just his memories. While that would be enough for a child without memories to become a "true" Masaki Wakatsuki, Masaki Akitsu's personality was too strong, and he eventually came to the realisation that he was simply being dragged along by how he thought he should be acting, thanks to Wakatsuki's memories, with Professor Himuro secretly watching. Deep in the base, Himura hovers over a switch, which would destroy the flawed Dimensional Joint in Miku's womb, killing both Miku and Masaki, but accepts that Masaki is not really Wakatsuki, and Miku is not his deceitful wife, feels guilt for considering Miku to only be a tool, and dies of his sickness. Upon finding him, Masaki decides that the only way to escape Zeorymer is by burying it himself, and decides to do so by attacking Nematoda's main base.

Arriving at Nematoda's base, Zeorymer's landing destroys many of its defending machines with the resulting shockwave, and makes short work of the remainder. Suddenly, the president of Nematoda appears, piloting a black Zeorymer, powered by the original Dimensional Fault installed into an "inhuman" Miku clone, revealing himself to be a second backup of Wakatsuki, but one with advanced aging thanks to the destruction left by the theft of the original Zeorymer affecting his regeneration. After the theft, he had killed the Nematoda president and taken his place. Fighting with Zeorymer and showing that they had equally powerful offensive and regeneration abilities, the two Zeorymer grappled and began to merge. Revealing that Zeorymer's power source was in another dimension, and that as a result, there can only be one Zeorymer, which was the reason that even Masaki couldn't make a perfect Dimensional Joint, despite having Wakatsuki's memories, the two machines merged into one, with the fake Miku collapsing, the original Dimensional Joint installing itself into Miku's womb, and Wakatsuki planning to take over Masaki's body in the process. Though Zeorymer is merged into a half-black, half-white version, Masaki, Miku and Wakatsuki were ejected from it. Wakatsuki fails to understand why, but Masaki enlightens him - Zeorymer reformatted its pilot registry when Masaki started piloting Zeorymer, and was installed with Wakatsuki's memories. Thus, Zeorymer couldn't install Wakatsuki's personality into Masaki's body. Wakatsuki's driven somewhat mad, reveals that he also has a self-destruct for the Joint in Miku's womb, but is shot and killed by Golshid, furious at Wakatsuki's murder of the original Nematoda president. However, there's a massive Deuterium Bomb under the Nematoda base, activated by Wakatsuki's death, which is large enough to destroy the world. However, Zeorymer is strong enough to survive. Rather than escaping, Masaki and Miku plan to absorb all the energy from the bomb's detonation into Zeorymer and into the other dimension. Golshid's expectation is that even Zeorymer will be destroyed, but Masaki says that he and Miku want to live, in this world that they grew up in. As they attempt it, Golshid is shown to have escaped in a pod. Though Masato and Miku succeed, the manga concludes by saying that no-one ever saw the G-Class Robot "Hades" ever again.

Set in the near future, a secret organization called Tekkoryū (鉄甲龍, lit. Iron Dragon), also known as Hau Dragon (ハウ・ドラゴン, Hau Doragon), is bent on world domination. Using the electronics firm International Electronic Brains as a front to fund their activities, Tekkoryū builds an army of eight giant robots known as the Hakkeshū (八卦衆, lit. Eight Trigrams), but Masaki Kihara, the scientist behind the Hakkeshū, betrays the Tekkoryū and steals Zeorymer of the Heavens (天のゼオライマー, Ten no Zeoraimā), along with the embryo of the pilot genetically linked to the robot. He dies shortly after handing Zeorymer and the embryo to the Japanese government. Fifteen years later, Yuratei ascends to the throne as Empress of Tekkoryū and orders the recovery or destruction of Zeorymer before proceeding with her plans to conquer the world.

An action figure of Zeorymer of the Heavens was released by Yamato Toys in 2007.[9] Bandai released Zeorymer in the Super Robot Chogokin toy line in 2012.[10] In 2022, Good Smile Company released model kits of Zeorymer and Great Zeorymer as part of the Moderoid line.[11][12]

Zeorymer was featured in the 2004 game Super Robot Wars MX for the PlayStation 2.[13]

• Hades Project Zeorymer (manga) at Anime News Network's encyclopedia
• Hades Project Zeorymer (anime) at Anime News Network's encyclopedia