- Awesome, Dear Boy: Yoshio Tsuchiya wanted to be in Godzilla (1954) film, but because he was doing Seven Samurai, he wasn't able to. He insisted in joining this film and Toho granted his request as Tajima. He would later join the franchise as alien invaders or possessed by one, something he enjoys.
- B-Team Sequel: While Shigeru Kayama, Takeo Murata, Eiji Tsuburaya and his special effects staff returned for the sequel, the film was directed by Motoyoshi Oda and the music was provided by Masaru Sato.
- Bad Export for You: The English version of Godzilla Raids Again commercially available on iTunes is nothing more than Gigantis: The Fire Monster with the original title slapped on it.
- DVD Commentary: The DVD release by Classic Media includes one by Steve Ryfle and a few others. It plays over and talks mainly about the American version, but it also talks about the Japanese version as well and how the movie in general compares to the original.
- Executive Meddling: Paul Schreibeman is the reason why the Gigantis film became what it was, because he said the renaming of Godzilla to Gigantis was to avoid confusion. He even said the original title was "Angurus" when the original name is Gojira no Gyakushu (Godzilla's Counterattack). This blatant attempt to pretend this is not a Godzilla sequel made it laughable to the original films of the franchise.
- On Toho's side, Iwa Omori, the head of Toho Studios, told Tomoyuki Tanaka to make another Godzilla film after the success of Godzilla (1954). Depending who you ask, it was the best or worst direct sequel.
- Follow the Leader: Sort of. Although this film marks the first time two monsters would fight each other in Japanese cinema, this doesn't mean the formula is anything similar to the film that really kicked off the "monster against monster" boom.
- Old Shame:
- Kaiju film regular Hiroshi Koizumi lamented that upon reviewing the movies he appeared in, including this film, he felt he hadn't realized his potential in them.
- Masaru Sato wasn't feeling for this film's score, citing "It's like listening to a kid trying to learn". Though he would later provide additional scores for the Showa series when Akira Ifukube wasn't available.
- Recycled Script: It's basically Godzilla (1954) with another monster added in. However, since Ishirō Honda was not involved in this film (he was directing a love story at the time), Shigeru Koyama wrote the script, with no alterations contributed from Motoyoshi Oda. However, without the original means to defeat Godzilla provided by Dr Serizawa, the Japanese are screwed.
- Refitted for Sequel: One of Godzilla's intentional names was "Angurius". The name would be used as Godzilla's first opponent here.
- What Could Have Been:
- Interestingly enough, Godzilla Raids Again wasn't intended to be merely dubbed and distributed. It was going to be called The Volcano Monsters where Godzilla would be just a Tyrannosaurus rex and Anguirus to be an ankylosaurus (how they were gonna explain a T-Rex that clearly looks like Godzilla is beyond us). Godzilla (or rather the T.rex), was to fight the ankylosaurus and move to the North Pole to lay its eggs. While Toho decided to help by sending new suits and made a catalog of the production, the American company went bankrupt and the suits disappeared. So, The Volcano Monsters was ultimately cancelled. This explains why it took a whole 3 years and why it wasn't released in that form. Eventually, the film ended up being called, to the massive face-palming of Steve Ryfle (and his fellow commentators) and fans everywhere, ''Gigantis The Fire Monster".
- A direct sequel was planned called The Bride of Godzilla where scientists create a female robot designed to kill Godzilla. Godzilla would have actually fallen in love with her, and take her to his colony of surviving Godzillas where she'd detonate a nuclear device which resulted a Downer Ending. This idea was never made and instead King Kong vs. Godzilla became the second sequel of the series.
- Anguirus had quite a couple prototype names before landing on the one Kaiju fans know and love. Among them were Gyottos, Zottos, Osoros and Sugon. It's not known who coined the name Anguirus however, but it turned out to be for the best, since it's one of the most well recognized names in the entire franchise!
Trivia / Godzilla Raids Again