Yakuza Zombie

Overview
Yakuza Zombie opens with an introduction to a mysterious Yakuza graveyard deep in the forest, and a story of the baddest Yakuza of them all, Naruo Ryuuji (shown in cut scenes played by Ozawa Hitoshi). Naruo Ryuuji was a fearless killer who eventually got into heroin and, exactly like Ishimatsu Rikuo in Takashi Miike's Graveyard of Honor, eventually leaps to his death from the top of a prison, claiming he'll be back. I'm assuming this is a reference to real life crazy Yakuza Ishikawa Rikio, whom the original Graveyard of Honor was based on. It's established that the corpse of the fierce Yakuza Ryuuji is buried in the graveyard beneath a marker with the Japanese characters "Jingi" (Honor), and then we are taken to the modern day.
Similar
True Record of an Ando Gang Side-Story: Starving Wolf's Rules (2002)
Exiled to Hell (1969)
Bad City (2022)
Yakuza vs. Gang Leader (1974)
Tattoo (2002)
The Shortest Distance Is Round (2019)
Music Box (1989)
Sonatine (1993)
Shinjuku Swan (2015)
The Clan's Heir is a Trans Woman (2013)
Wolves, Pigs & Men (1964)
The Quiet Don: Chapter 1 (2023)
Unification of Japan Gaiden: Yamazaki Ichimon 8 - Metropolitan Police Department vs. Yamazaki Ichimon (2023)
Motorpsycho! (1965)
Overkill (1987)
Gambling Den Desire (1970)
Versus (2000)
Fireworks (1997)
Unification of Japan Gaiden: Yamazaki Ichimon 7 - Yamazaki's Little Love (2023)
Dead or Alive 2: Birds (2000)