Also known as Manual of Ninja Martial Arts, the only animation from Japanese New Wave maestro Nagisa Oshima is as provocative as one would expect from such a remarkable filmmaker. The film follows Sanpei Shirato's classic comic story about the son of an assassinated feudal lord in the Muromachi period, who attempts to avenge his father's death and meets Kagemaru, a renegade ninja helping peasants and farmers rebel against Oda Nobunaga's regime.

[Source: MyAnimeList]

An animated pilot film for Ninja Bugei-chou released to the public over three decades later on Ninpuu Kamui Gaiden DVD volume 7.

The pilot film was created in 1969 as director Nagisa Ooshima was wanting to make a TV animation to build off his controversial film from 1967. The pilot was rejected by Shirato himself (the original comic creator the film was based on) and the plan was changed to animate Ninpuu Kamui Gaiden instead, a side story to the Kamui Den manga also created by Shirato. Though with this change, Ooshima did not partake in Ninpuu Kamui Gaiden's production.

[Source: MyAnimeList]