This was the first giant monster film produced after the death of Toho's special effects director, Eiji Tsuburaya, who passed away in January 1970. Sadamasa Arikawa was promoted to to Director of Special Techniques (special effects) and Teriyoshi Nakano was promoted to his chief assistant.
All three monsters, the squid Gezora, the crab Ganimes and the turtle Kamoebas have remained relatively obscure and never had a major role in later monster movies made by Toho. However, Gezora gained some notoriety for its appearance as the first boss in Nintendo's Godzilla: Monster of Monsters video game and its brief cameo in Gojira: Fainaru uôzu (2004), and Kamoebas also had a cameo as a carcass washed ashore in Gojira tai Mosura tai Mekagojira: Tôkyô S.O.S. (2003).