A team of super-skilled criminals roams a science-fiction Wild West, each with their own reason to hunt for the ultimate prize: the 12 Rings of the Dead, which can raise the dead and grant eternal life.

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... All volumes except the first also contain a bonus short story by Tite Kubo: Ultra Unholy Hearted Machine (vol. 2), Rune Master Urara (vol. 3), and Bad Shield United (vol. 4).

A knife-thrower. A sharp-shooter. A martial artist with a metal hand. And now...a journalist?! Meet the newest member of Gamma Akutabi's gang, the amazing Wolfina, as deadly with a camera as her friends are with a gun. Their goal is to find the Rings of the Dead...but only Wolfina knows the Rings' true twisted nature firsthand, having seen them turn her brother into a mindless husk. Does the secret of eternal life now dwell in her brother's body? And what kind of human vultures would pry the secrets from his remains? Includes a special bonus story, "Ultra Unholy Hearted Machine"!