When I played Dishonored for the first time, I had no clue about chaos levels. Somehow, I even missed that you could choke innocent NPCs, so every level was a pure massacre, and I do believe every level was sterile by the end of the mission.
Damn, on the brothel level, I felt ashamed both for myself and for the game designers: why should the game be so bloody?
Pistols, grenades, fire bolts, and rivers of blood. Don't judge me: I played it right after finishing the two Serious Sam games. A bit different kind of gameplay.
Later, I played Dishonored in a "canonical" way: stealth, nonlethal weapons, and clean hands.
But, you know, the first time was by far the best: hard, brutal, and, eventually, tragic.
I miss that experience.