ZOMBIEPOWDER.

Overview

Somewhere in the desert lies the world's greatest treasure: the 12 Rings of the Dead, the only source of the mysterious substance Zombie Powder, which can raise the dead and grant eternal life. Into this world stalks Gamma Akutabi, a man with a metal arm and a six-foot chainsaw, cybernetically enhanced master of the legendary martial art . But it takes more than one man to find the ultimate prize. You need a team: super-gunman C.T. Smith, knife-slinging teenager Elwood, and brilliant (and impossibly big-breasted) journalist Wolfgangina. Against an army of crooks and killers, against runaway trains and superpowered madmen, they'll need all their skills... but the most dangerous thing in the west might be the Rings themselves... (Source: VIZ Media) Note: Includes eight extra chapters.

Source: AniList