The citizens in Dishonored 2 have had a bad time in the city of Karnaca, thanks to the corrupt guards, swarms of bloodflies, and their new empress being an angry witch. Thankfully, you can make a few of their days brighter by interfering with guards and Overseers bothering them. One of the earliest opportunities will be in Chapter 2 as you are exploring the early parts of the port area. In order to unlock the “Stay of Execution,” you will need to save a civilian from being pushed into the Wall of Light.
When you load up Chapter 2, head towards the black market first and make sure to pick up some sleep darts from the vendor. Quickly make your way down the road to your right, making sure to keep just above street level via awnings, lamps, and balconies. Once a menu pops up on your screen indicating your different approach options, you will only have a few seconds to stop the guards.
As soon as you exit the pop-up screen, turn left at the fork and hit both guards by the civilian with sleep darts. There will be one more soldier stationed to your right on a balcony so make sure to take care of him as well if you want to go unnoticed. After all three men are knocked out or dead, the civilian will run off and the trophy/achievement should pop. This is perhaps the only location you can actually do this in, so make sure to save beforehand in case you mess the timing up. If you are using Corvo, Bend Time is fantastic for this sequences as it will give you ample time to put down all three men before they even know what happens.
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