Joining Marvel's editorial staff in 1980, O'Neil edited "Daredevil" during Frank Miller's run as writer/artist. He fired writer Roger McKenzie so that Miller could both write and pencil "Daredevil", a decision which then-Marvel editor-in-chief Jim Shooter says saved the series from cancellation. O'Neil encouraged Miller to develop a believable fighting style for Daredevil, and according to Miller, this directly led to his incorporating martial arts into "Daredevil" and later "Ronin". In the early to mid-1980s, O'Neil edited such Marvel titles as" Alpha Flight", "Power Man and Iron Fist", "", and "Moon Knight".