The multiverse begins to overlap thanks to Mad Origin controlling the Gridman Universe.
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As the multiverse begin to overlap, residents of other worlds begin to appear before Yuta and his friends. Manaka, Minami, Yume, Yamanaka Koyomi, and Asukagawa Chise are reunited with Rex (Gauma) and end up staying at Rikka's house like the new century middle school students. During the commotion, Yuta learns that the college student who was suspected of being Rikka's boyfriend is her older brother. Yuta is relieved, but a ghost-like shadow appears in front of him again, ruining his mood for confession. While going shopping with Mama Rokka and Koyomi, Gauma has an unexpected reunion with his beloved Hime, who he lost 5000 years ago.
Hime the princess from 5000 years ago is reincarnated in the modern world due to the overlapping parallel worlds.
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5000 years ago, a princess of a certain country had monsters, Gauma, and other monster tamers as her servants. She entrusted Dynazenon to Gauma, who was her lover and had promised their future to each other. When a conflict broke out between her home country and the monster eugenics ideaology, and she learned that Gauma had lost his life, she decided to follow in his footsteps. As parallel worlds overlap and chaos spreads, she reincarnates in the present day and reunites with Gauma for the first time in 5000 years in an unexpected place. There, she tells him the "three things a person should protect" that she has repeatedly told him, and tells him to look to the future and not drag on her past. While we see har kindness, nobility, and strength at heart, she also shows a strangely frank side.
Info on Mad Origin, who seeks to destablize the universe/multiverse by using Gridman.
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Mad Origin (1st form)
MAD ORIGIN CV: Nenshi Kannobu
The culprit behind the incident, who uses Gridman under his evil intentions to accelerate chaos, disrupt the balance of the universe, and bring everything to an end. Because it retains Gridman's memories, it was a formidable enemy that none of Gridman's or Gridknight's weapons could penetrate, but Chise's quick thinking allowed him to defeat Rogue Kaiser Power Finish when he attempted to fuse with him for the first time.
Mad Origin's second form after absorbing Alexis Kerib gained the power of infinite life (immortality), but was defeated by the powers of creation and destruction wielded by Gridman and the heroes.
Mad Origin (2nd form)
The form in which Mad Origin absorbs Alexis Kerib, gains infinite life, and is revived. When it constituent materials deteriorated due to the simultaneous attack of the powerful Gridbeam Hyper Fixer Beam spewed from its mouth, it was crushed by Gridman and destroyed. Its weapon is Full Power Grid Rex Roar.
Gridman the Universe Fighter is Gridman's mew form after being rescued from being Gridman Universe. He dragged Mad Origin into the world from outside for the final battle, and possesses both regenerative and destructive abilities.
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Gridman (Universe Fighter)
GRIDMAN [Universe Fighter] CV: Hikaru Midorikawa
Gridman, who was about to collapse the universe that made up himself because Mad Origin took advantage of his debt of having taken away Yuta's memories, even if it was temporary, is trying to overcome Akane's power, Yuta's feelings, and everyone's feelings. A new appearance brought to life through imagination. The exterior is based on a Gridman drawn by Yuta and his friends, and he drags Mad Origin, the culprit behind everything, from "outside the world" to Azalea for the final battle. He has both the power of destruction and regeneration, and when its power is activated, the lines on his entire body glow in rainbow colours. His abilities have also become more powerful than before, and the Gridbeam he fires from his left arm can damage monsters and repair the destroyed world at the same time. He can combine with Dynazenon and Big Goldburn to become Rogue Kaizer Gridman, and can also be combined with Big Goldburn alone.
There are many worlds that were created by Gridman, including the world of SSSS.Dynazenon, which also includes all the manga and novels; though the writers and staff had debates about if it was ok that Yomogi and his friends and story came from a world invented by Gridman.
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The previous plot, in which new guests played a large role, shifted towards the finished product, and Mr. Amemiya came up with the big mysteries. The idea is that the worlds depicted in novels and manga, including the various worlds "SSSS.Dynazenon," are born from Gridman's memories of becoming one with the universe, and that they all exist in parallel. As they merged, the members of SSSS.Dynazenon appear on the Azalea. However, there was also a debate about whether it was really ok. Is it ok to say that the story of Yogi and the others was all a made-up world? And SSSS.Dynazenon did not mention the origin of the world, so I think it would be a big shock for viewers who came from there.
Tetsu Inada, the voice of Alexis Kerib, states that Akira Amemiya has a secret image of Alexis Kerib as Chief Overjustice from Space Patrol Luluco (it's important to note that Tetsu Inada voices both characters). Also, this idea was originally Amemiyas.
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As for the backstory, director Amemiya seems to have a secret image of the character Alexis Kerib as the end of the Overjustice Headquarters in the work that director Amemiya directed called "Space Patrol Luluco." He is said to have arrived after wandering alone for thousands or tens of thousands of years. So, I think I received the Fixer Beam in the final episode of SSSS.Gridman and returned to being the head of Overjustice (lol). In the first movie, when Akane used Instance Domination, I added a voice that sounded like Ultraman's, saying "Shah!", but during the test, I shouted "Justice!" as loud as I could. If you have to decide whether it's good or bad, it's not (lol).