This chapter is a complete guide for Fatal Inheritance quest. Here you can find tips that will help you to finish this quest in the most beneficial way.
Activating the quest
The quest appears in your journal after you speak with Ranaman. When you are closer to the Village, you can hear a loud conversation between him and a guard so you certainly won't miss it. He asks Aloy to go to his mansion and find out if his family is alive. He ran away from the mansion because it was attacked by machines.
Defeat the machines
When you get behind the mansion's walls you can quickly learn that the machines still are there. Your goal is to eliminate them so you can calmly run an investigation on the survivors. You shouldn't have much problems with getting rid of the machines because there are many bushes. The only hindrance can be the Ravager but you should be able to defeat it by using traps and fire.
Check out the mysterious device
When you defeat the machines you must enter the workshop, on the left from the main gate. The doors are closed but on one of the walls you can find a few stones that can allow you to climb the wall and get on the workshop's floor. When you are inside the building you must get to the lower floor and use Focus to find the source of weird noise. When Aloy turns off the device, you can leave the workshop.
To continue the quest you must get closer to the mansion. You can hear screams coming from behind the doors on the left. Use interaction button to unlock the door. You must watch a short cut-scene and after that you must fight with the Glinthawks. Remember that the fire works the best against them. After a while, they will fall to the ground.
Finishing the quest
After the fight, speak with Daradi. She will explain Ranaman's motivations. This ends the quest and you receive your reward.