- Big Name Fan: Koichi Kawakita, who provided the special effects throughout the majority of the Heisei Godzilla films, is a fan of the movie. He even provides the audio commentary on the films DVD release.
- Creator's Favorite: Director Ishiro Honda has cited this as his favorite film he directed.
- Dueling Dubs: The film has been dubbed into English twice. Once in 1958 (theatrically exhibited in 1959 by MGM after RKO went bankrupt), and again in 2005 by Bang! Zoom for the Media Blasters DVD. To put it quite bluntly, the newer dub is essentially sacrilege, because the original dub was perhaps the most tasteful, unaltered English version of a Toho Sci-Fi film at that time, and they would've been better off finding usable elements of the RKO version instead. At least two decent 35mm prints are known to exist in the hands of private collectors. You can get a feel of just how dreadful the new dub is here.
- Executive Meddling:
- Ishiro Honda originally wanted to make the film without a giant monster, but Tomoyuki Tanaka insisted that there be one. Thus, the Moguera was born. Not that this is a bad thing, mind you.
- This is the reason the RKO version was not present on the DVD. Toho refused to allow Media Blasters to use the RKO dub for their release, forcing them to use a new, worse sounding dub.
- Keep Circulating the Tapes:
- The only way to watch the original RKO/MGM U.S. version outside of actual film prints.
- The Media Blasters DVD has also fallen into this after going out of print.
- Limited Special Collector's Ultimate Edition: While not billed as such, and certainly not when compared to collector's editions of other films, the US DVD from Media Blasters might as well be called it, since it has so many special features, including five audio tracks, one of which is a Japanese audio commentary with optional English subtitles, trailers, image galleries, and an anamorphic widescreen presentation of the film. Back when the DVD was released, seeing so many features on a US DVD of a Toho film was almost unheard of, with the exception of ADV's DVD releases of the Heisei Gamera Trilogy.
- Typecasting: This film, along with Godzilla (1954) is the reason why Momoko Koichi went to stage acting, since people have often known her as the actress from Godzilla. She appears to soften up a bit and reprised her famous role in Godzilla vs. Destoroyah.
- What Could Have Been: Moguera was originally going to be a reptilian mole-like kaiju, but was changed mid-production into a mole-like mecha (the first of many for Toho) instead to differentiate it from all the other reptilian kaiju Toho was making around this time (while still retaining most of the visual features of the original design).
Trivia / The Mysterians