Read every single file in the story.
Get up your map, press LB to go journal, go down to see files and the press Y to list them.
Your list should look like this for the achievement
1. Fridge memo
2. Old news clipping
3. Ethan diary
4. Medical checkup report
5. Mission briefing
6. Scribbled note
7. “Goats of warding” placard
8. Dangerous creatures
9. Guest book
10. The labyrinths
11. Winemaking history
12. A maids diary
13. Treatment candidates
14. Observation report
15. A cook’s diary
16. Alcina dimitrescus diary
17. Grand chambermaids notice
18. Further observations
19. Insect observations journal
20. Rumors of a dagger
21. Craftsmans note
22. Leonardo’s message
23. Note on the luthiers house
24. Eugens diary
25. Church computer
26. Gardeners diary
27. Vasiles final testament
28. The reservoir and the giant fish
29. Changing the cranks
30. Moreaus diary 1
31. Moreaus diary 2
32. Moreaus diary of experiments
33. Analysis results
34. Ernests diary
35. Officers diary
36. Experiment notes
37. Development note 1
38. Development note 2
39. Sturm
40. Heisenbergs diary
41. Chris’s computer
42. Dimitrescus medical report
43. Donna’s medical report
44. Moreaus medical report
45. Heisenbergs medical report
46. Spencer’s letter
47. Miranda’s diary