Mastery, also known as Proficiency (熟練度, Jukuren-do?), is a leveling system for Special Arts and Symbology in the Star Ocean series. It allows these skills to grow and improve over time through steady usage, increasing their effectiveness or even changing the execution of the ability entirely.
A Mastery counter is not actually visible in Star Ocean, but the usage of special arts is recorded. Special Arts that correspond to advanced arts via Secret Fighting Techniques must first be "mastered" through a number of uses (numbering the hundreds) before the new technique can be learned in combat. In First Departure, the mastery system is like that of Second Evolution.
Known as Proficiency in The Second Story, most special arts and symbols record a character's uses up to 999 times. Most individual abilities have their own 'level' of proficiency points before they improve one or multiple times; the amount of uses to improve each art and spell vary.
All battle skills, passive and support skills, and most symbols have ten levels of Mastery, slightly improving in some way with each increase in level. The Mastery points needed to reach a level varies from skill to skill. The only way to increase character's proficiency with skills or spells is through use. Passive and support skills, like Stun or Max Fury, increase only when their effect is triggered.
Their leveling-up patterns are as follows:
|Pattern||Lv. 2||Lv. 3||Lv. 4||Lv. 5||Lv. 6||Lv. 7||Lv. 8||Lv. 9||Lv. 10||Total|
As in the previous installment, special arts and most symbols have ten level of mastery, but unlike the previous installments, this time they improve by spending CP. As the skills rank up, not only its base power but its MP cost goes up as well.
- In Star Ocean: Anamnesis, the base power of a character's abilities can also increase; however, this is done through the Awakening system rather than through mastery.