Seigi Chōjin vs. Ancient Chōjin (正義超人vs古代超人, Seigi Chōjin tai Kodai Chōjin) is the third theatrical film based on the anime series Kinnikuman. It was released in Japan on March 16, 1985 and is set after the Golden Mask Arc.
This film is the first to feature anime original character Kinkotsu-Obaba. Although this film is set after the Golden Mask Arc, the character Geronimo does not appear as an active fight until the next film. He does, however, appear in flashbacks to the Golden Mask conclusion. This is also the second time veteran seiyu Ichiro Nagai appears in a Kinnikuman work playing the main villain. He had previously appeared in the TV Special. It also features the return of seiyū's Kozo Shioya and Yasuo Tanaka, who had previously appeared in the first film The Stolen Championship Belt.
- Koichi (幸一くん Kōichi-kun)
- Satan King (サタンキング)
- The boss of the Kodai Chojin from Mount Everest.
- Stone Satan (ストーンサタン)
- A Moai chojin from Easter Island. He is similar to Moaiman.
- Condor Satan (コンドルサタン)
- A condor chojin from the Nazca Lines
- Eye Satan (ガンサタン, Gan Satan)
- A cyclops chojin from Tassili n'Ajjer.
- Jaws Satan (ジョーズサタン)
- A Merman chojin from Atlantis
- Cobra Satan (コブラサタン)
- A Cobra chojin from Mu.
- Haniwa Satan (ハニワサタン)
- A Shakōki-dogū chojin from Aomori. Not actually a Haniwa, he is similar to Doguman.
- Saurus Satan (ザウルスサタン)
- A reptilian Chojin from Palenque.
- Ukon III (ウコンⅢ世, Ukon Sansei)
While Kinnikuman is on vacation with Mari-san's kindergarten class at Easter Island, the young wheelchair-bound Kōichi laments being with an idiot like Kinnikuman, preferring to instead be with his favourite Seigi Choujin Buffaloman. Meanwhile, the other Seigi Choujins are also vacationing at ancient landmarks.
The "Space Ruler" Satan King (サタンキング) has his Kodai Chōjin (古代超人, Ancient Supermen) attack Kinnikuman, Terryman, and the other Seigi Chōjins. Long ago, Satan King had secretly sent his subordinates to Earth to wait for the right moment. Each Seigi Chōjin is able to survive their battles with their trademark techniques, but Satan King takes Mari-san's kindergarten students hostage and summons the Seigi Chōjins to Mount Everest. One by one Satan King's subordinates attack and the Seigi Chōjins are critically injured. Finally, Satan King has conquered Earth and laughs loudly. At that moment, Kinnikuman arrives and the single greatest decisive battle for the world begins. Satan King attacks Kinnikuman with his ice and lightning attacks, making him dizzy, but he recovers and defeats Satan King with his New Finishing Move the Kinniku Driver.
- Opening Theme
- Blazing Kinnikuman (炎のキン肉マン, Honoo no Kinnikuman) by Akira Kushida
- Closing Theme
- Kinniku Mambo (キン肉マンボ) by Akira Kamiya (Kinnikuman)
- In the previous film, Daisuke Gōri played the opponent of Masashi Hirose's character. This time Hirose is playing the opponent of Gōri's character.
- This is the second Kinnikuman film where Issei Futamata plays Ramenman's opponent. He had previously done this in Great Riot! Seigi Chojin. He also played Ramenman's opponent in the 1984 TV Special.
- Terryman is wearing his normal clothes during his initial fight with Saurus Satan, but during the close-up of the Calf Branding he is wearing his wrestling attire. This occurs again when the Seigi Chojins are watching Warsman's fight: for most of the scene he is wearing his normal clothes, but in one group shot from behind he is clearly wearing his wrestling attire.
- At one point during Kinnikuman's battle with Satan King, the Chairman's head-fin is not coloured in.