In ‘Once Upon A Time’ No.6 refuses to kill, because he’s afraid to step over the threshold, according to No.2 that is. And no amount of provocation will make No.6 kill. In 'Living In Harmony' as a Sheriff the Man With No Name, hands in both his badge and gun, this in an act of resigning his job. And when he finally allows himself to be recruited by the Judge, but only for the sake of Cathy, he still refuses to wear a gun. He refuses to pick up a gun when challenged by the Kid. And yet, when the Man with No Name does put on his gun, overcoming his reluctance to take up the gun in the name of vengeance, the result is quite devastating. He takes on three of the Judges gunslingers in a fire-fight, and the Kid, who he stands against in the street, leaving all four dead. Finally proving to the Judge that the Man With No Name is the fastest on the draw he’s every seen, is ever likely to see. Because the Man With No Name has a conscience, and already regrets what he’s done, and he resigns. There is armed insurrection in ‘Fall Out,’ and the former No.6 has no qualms about indiscriminately gunning down the armed security guards. It would seem that in certain situations, and according to circumstances, that the Prisoner will step over that threshold, and is as capable of killing as anyone.