The Third one works for me. Though Cadmus doesn't kill innocents, he's not a villain. But what if he kills someone Lucias perceives as innocent? Cadmus also has a personal vendetta against a group called the Iron Claw because they murdered his mother, in his history, Cadmus let one of the men go because he was against killing, but then this man went and killed his mom. Cadmus never managed to get him back for that, what if Cadmus kills the man and Lucias was protecting him, or Lucias witnessed it and believed it to be unjust?