Sword of the Apocalypse

You play as the wandering Ronin—Kaze—or the deadly gunslinger—Forge—who come into possession of a mysterious necklace. It's previous owner's dying wish is not to let the cult get it, no matter what. What they don't realize is that the necklace is actually one of a pair of nuclear arming keys. The other key is held by The Cardinal, a dangerous extremist who wants to use ancient doomsday weapons to bring about human extinction. Kaze and Forge must face the cult head on to put a stop their nuclear attack on New Chicago. If they fail, tens of thousands of people will die in an instant.