Yasuei Yagi (Yagi Yasuei), known collectively with his brother Kanju as the Yagi Brothers, was a Japanese sculptor and modelmaker. The first known film Yagi worked on was "Godzilla" (1954), and he (alongside Kanju), would continue to do modeling and sculpting work on Toho's Tokusatsu films, such as "Mothra" (1961), "Atragon" (1963), "Frankenstein vs. Baragon" (1965), as well as the Daiei Tokusatsu film "Gamera the Giant Monster" (1965). Following Kanju's death in 1966, Yasuei continued modeling and sculpting work on Toho's Tokusatsu films until "Space Amoeba" (1970), after which Toho's in-house special effects department was closed. Many Toho staff stopped working on their films after 1970, so it is unknown if Yasuei never returned for another film from Toho due to the effects department closure, or if he also passed away shortly after his last film.
