Here is the full list of all 17 Return of the Obra Dinn trophies - there are 2 bronze, 4 silver, 10 gold and 1 platinum.
Get all trophies
Solve the entire book.
Solve all fates in chapter IX.
Solve all fates in chapter VII.
Solve any 45 fates.
Solve all fates in chapter X.
Solve all fates in chapter VI.
Solve all fates in chapter V.
Solve all fates in chapter IV.
Solve all fates in chapter III.
Solve any 30 fates.
Solve all fates in chapter II.
Solve any 15 fates.
Solve all fates in chapter I.
Solve any 6 fates.
Loosely true, in the eyes of Company and Crown.
Leave the ship without solving all available chapters.