Quote Originally Posted by PraetorDragoon View Post
Dishonored is sometimes..... not the best at showing the consequences of your actions. Sometimes its good at it though.
With respect to Campbell:

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If you don't kill him, it's possible to find him as a Weeper in one of the later missions--which just goes to show that the "non-lethal" option in Dishonored is often worse than just flat out killing them!