OCTOPATH TRAVELER

This comes by playing and exploring the game you need to get every subclass and secret jobs by going into every Shrine the subclasses unlock at the end of every shrine and the secret jobs unlock at the end of every shrine fighting the boss wielding the secret job. After unlocking every class you need to unlock the skills which unlock support skills and lead to this achievement. This also unlocks the achievement for every skill unlocked + the achievements you get for learning and mastering every class