Alternately, you can risk shooting the NPC with a Sleep Dart (resulting in a massive swarm of rats) but that will immediately disable the NPC and prevent it from respawning a version that can detect you.

One choice will always brand you as a killer, but incur no alerts the second choice easily results in no fatalities, but it may be extremely difficult (if not impossible) to evade detection (unless you use Bend Time at maximum level at the right moment). Beware that in the mission Flooded District, Corvo will need to make a mandatory decision between two NPCs.This naturally, will disqualify you from Clean Hands. Killing enemies is an option, so you may find the occasional stealth kill using a crossbow very helpful. For Ghost and Faceless, you cannot be spotted at all (the Metal Gear Solid Stealth Syndrome).For Clean Hands, the Combat Sleep Dart is a very handy purchase, since that is Corvo's only non-lethal ranged attack.Handle Clean Hands by itself, unless you feel like using a Save History as your extra 'weapon' to save and reload all your failures at being seen or spotted (for Ghost and Faceless).Remember that killing anyone will negate the Clean Hands achievement (have no kills for the entire game), which is what the Low Chaos walkthrough pages are for. Medium chaos isn't a game state - it's merely there as a guide to playing the game on Low Chaos with an occasional kill or battle here and there (where it would make things easy to kill everyone).

Walkthrough for dishonored 2 mission 7