Weapon mastery skills

Weapon mastery skills are a group of passive skills available to most classes at 2nd job (with the exception of INT Cleric, Ice/Lightning Mage, and Fire/Poison Mage), which passively grant their users significantly higher minimum damage when using the type of weapon specified by the skill. Additionally, they passively grant accuracy when using the weapon specified.

There are 11 weapon mastery skills in total:
 * Sword Mastery (Fighter/Page)
 * Axe Mastery (Fighter)
 * BW [Blunt Weapon] Mastery (Page/virtual skill for 2nd job Battle Priest)
 * Spear Mastery (Spearman)
 * Polearm Mastery (Spearman)
 * Bow Mastery (Hunter)
 * Crossbow Mastery (Crossbowman)
 * Claw Mastery (Assassin)
 * Dagger Mastery (Bandit)
 * Fist Mastery [previously known as Knuckle Mastery] (Brawler/2nd job Monk)
 * Gun Mastery (Gunslinger)

Skill description
To understand the effect that the mastery given by these skills has, we must look at an abstracted form of the damage formula (credit to Ayumilove's Formula Compilation): MAX = (Primary Stat + Secondary Stat) * WATK / 100 MIN = (Primary Stat * 0.9 * Skill Mastery + Secondary Stat) * WATK / 100 Here, "Primary Stat" refers to the primary ability used for the weapon, multiplied by that weapon's "damage multiplier", e.g. for a one-handed sword this is (STR * 4.0). "Secondary Stat" is the secondary stat used for the weapon, e.g. for a one-handed sword this is (DEX).

"Skill Mastery" is equal to 0.1 by default, for those who do not have any mastery skills that apply to the weapon they are using. The "mastery" listed by the weapon mastery skills applies here directly; e.g. at max level of the Sword Mastery skill, the skill reads "Sword Mastery 60%...", which means that the value of "Skill Mastery" is then 0.6.

Note that this does not affect the maximum of one's damage range.

Levels
Note that this table applies for all mastery skills.

Special interactions
The Fist Mastery skill (Brawler/2nd job Monk skill) affects to magic damage dealt by the Perfect Strike skill, which means that it is incredibly important for the melee damage output of Monks. The damage formula is a little bit different for Perfect Strike: MAX = (INT + DEX) * MATK / 100 MIN = (INT * 0.9 * Skill Mastery + DEX) * MATK / 100

Compared to vanilla v62 GMS
The only changes made to these skills are the special interaction listed above with the Perfect Strike skill, as well as the ability for 2nd job Clerics (Battle Priests) to take levels in the BW Mastery skill as a virtual skill, up to level 12.