[1][2] There were originally three movies made: While not canonically linked, all three were thematically joined by their inclusion of a group of creatures from Japanese mythology known as yōkai (妖怪, lit.
Receiving little attention outside Japan, the films are remembered mainly for their special effects, which include a lot of puppetry, suitmation, and even traditional animation.
The film is not officially related to the Yokai Monsters trilogy, but draws a lot of its influence from similar sources, notably the legend of Momotarō and Shigeru Mizuki's GeGeGe no Kitarō series of the same name.
[7] Mizuki himself appears in this version, though neither the remake nor the original films make use of his yōkai creations, preferring instead to feature more traditional creatures.
[9] Yōkai Heaven and its sequel Yōkai Heaven Ghost Hero by Makoto Tezuka in 1986 and 1990, and Sakuya Yōkaiden in 2000 were released by different companies, however these films were redeveloped from reboot attempts of the Yokai Monsters by Daiei Films and Tokuma Shoten, also appointing staffs previously involved in the Gamera franchise including the director Tomoo Haraguchi and others such as Shinji Higuchi.