Meanwhile, Bilusaludo commander, Galu-gu is elated to discover that the Houtua tribe's arrowheads are made of a nanometal or a self-sustaining metal. It had been developed in the 21st century as an "anti-Godzilla" killer weapon deployed at their decisive battle fought at the foot of Mt. Fuji, but had been destroyed before it could be activated in the form of a "Mecha-Godzilla." The nanometal was its base substance, and proof that the manufacturing plant can still be used.
The film is animated by POLYGON PICTURES is directed by Kobun Shizuno (Fist of the North Star: The Legend of Kenshiro, various Detective Conan films) and Hiroyuki Seshita (Ajin, Knights of Sidonia) with Nitroplus's Gen Urobuchi (Kamen Rider Gaim, Fate/Zero) credited for the film's concept and screenplay. Lastly, the XAI returns to perform the film's theme song, "The Sky Falls".