Every job comes with a list of weapons that can be equipped, skills that are enabled for use, and abilities for passive benefits. Jobs also give additional skills and abilities by leveling them up, through Job EXP via battling or consuming seeds. A job is considered "mastered" at level 10 and cannot level further, but most jobs unlock stronger versions once mastered. A mastered job is marked by a star at the job selection screen..
Jobs are a key factor in defining what weapons a character can use, as well as how they can currently spend their ability points.
Jobs can be freely changed by the priest at Ilias Temple.
Some jobs require a Job Change Item before it can be selected, which are found throughout various locations in the world.
Basic Jobs are the beginner jobs and are mostly for testing out playstyles and roles for certain characters. They level up quite fast because of it.
Intermediate Jobs are for when you know what role you want a character to play and wish to make them stronger, but they take longer to grow.
Advanced Jobs are unlocked after you complete significant events and will lead your characters to become even more powerful. They take even longer to master as expected.
Sealed Jobs are a exclusive type of jobs that top Advanced Jobs. None are currently available, and there are only rumors about them that can be heard from a Valkyrie located in Snow Heaven's Blacksmith.