This trophy starts in the Advent Palace in Act 1: Middle East. You need to defeat the enemies in this area with non-lethal means, which means you need to deplete their psyche gauge instead of their health gauge by using CQC, sleep mines, Mk. 2 pistol, etc.
Go through the Advent Palace until you get a cutscene (look out for the sleep mines on the floor, if you run into them just wiggle L3 left and right until Snake wakes up. There are also claymore mines scattered around the place which will damage you, so I'd advise just shooting them from a distance to set them off.) After the cutscene equip your non lethal weapons of choice, leave the room you're in and go down the stairs. Follow the people you're with through the building while knocking out the enemies (don't worry about the AI killing them, that doesn't matter). After fighting your way through the building you'll drop down an elevator shaft and end up in a garage. If you look behind you, you should see the doll on the floor next to the doorway.
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