1. Make sure that you find and save every little sister in the campaign. You get the option to save when you have a little sister and you are at a vent. Now, you meet Grace at Paupers Drop. She is the first one you meet. You'll meet her pretty much at the end when you infiltrate her hideout full of splicers. When you find her in her secret place, she'll open her door and you have the option to kill her. Don't hurt her and just get the item and leave the room. The door will close and she will start saying stuff to you through the radio, audio, whatever it is. The second person you meet is Stanley. You meet him at Dionysus Park. You meet him early in a locked train room. You have to do some stuff before the door unlocks. Then when your going back to the train at the end, Lamb will open the door so you can decide his fate. Just go in the room and pick up items if needed but don't hurt him and just go in the train and leave. Finally, you meet Gil at Fontaines Futuristics. This guy is crazy and annoying. At the end you get to a dark lab with a huge tank. Gil wants you to find plasmid plants before you can decide Gil's fate. After collecting, you put the adam in the tube. After, Gil will tell you to kill what's inside, and there will be a switch that flashes(not gold). Don't press it, just leave the lab and go to Lamb's hideout. After reaching the hideout, the achievement unlocks.