Editing the review after having rewatched the film (in addition to having watched parts 1 and 2).
First, it's important to say that I don't consider it necessary to watch the previous ones to appreciate this masterpiece (but I recommend it if you're interested in the story as a whole).
The leap in quality of script, acting, special effects and message is huge compared to its predecessors and even today (August 2024), the experience is very pleasant and has not been harmed by the "aging" of the film.
This film, unlike the previous ones, finally inserts Buddhist elements into the story in a more precise and non-parodial way, which in my opinion was a great benefit.
Drawing a comparison, it is very common in film production for the protagonist to be driven by hatred and desire for revenge and all the elements in the film justify such conduct.
In this film, on the contrary, the protagonist is driven by the desire to help all beings, including demons. Oh! This practically sounds like heresy to many of us, doesn't it?
Furthermore, the film shows that the greatest power has nothing to do with physical strength or superhuman powers, while delivering great fight scenes and great special effects (taking into account the natural aging of an 11-year-old film).
More than ever, I highly recommend this film to any human being who seeks to be better and to free themselves from suffering and the causes of suffering.