Equipment Modifiers

Aptitude

Each job has their own aptitude towards certain weapons and armor. Aptitudes are measured by rank. Letter S is the best aptitude while E is the worst. A character can equip a rank E equipment but will only receive the equipment's base stats. However, when equipped by a character that has S-rank aptitude towards that equipment can enjoy double the equipment's base stat.

The bonus a character gets for each rank are the following:

For example, a Performer has S-aptitude towards rods, staves and daggers while an A-rank aptitude towards swords. When you equip an E-rank weapon, let's say the axe Labrys (P.Atk = 53), it will only add 53 points towards to the character's unarmed physical attack rating.

If you equip a Performer with a staff, in this example a Diamond Staff (P.Atk = 38), that character will will 76 points to her P.Atk rating instead. The staff has lower base power but it is doubled when equipped on a character that has an S-Rank aptitude towards that weapon.

Unarmed Stat Bonus

The Monk class is a bit different though. They have S-Rank aptitude towards knuckles but their specialty, Knuckle Lore will allow them to get a physical attack bonus twice their level if no weapons are equipped. A LV99 Monk will get a 198 attack bonus unarmed than equipping a Kaiser Knuckle (P.Atk = 95 x 2).

When a Monk reaches the maximum job level (JLV14), he/she learns Natural Talent, a support ability that raises the attack by 100% when there's nothing equipped on their right hand, left hand, head, body and accessory slots. The outfit/ costume slot has no effect on this.

Dual Wielding

The game allows you to equip two weapons at the same time (except for two-handed weapons like bows and knuckles). However, the weapon's stat modifier will be halved to compensate with the additional weapon. A character with Dual Wield support ability (Ninja's have this as their specialty) can equip two weapons on both hands without the weapon modifier penalty.

In the other hand, the ability Two-Handed will allow a character to hold a weapon (except daggers, maces/rods, bows and knuckles) with both hands, doubling its power. This stacks with the weapon aptitude bonus so giving a character with the Two-Handed and Sword/Axe/Spear/Staff/Katana Lore (for jobs that're not quite compatible with those weapons) renders the best results.

Weapon / Shield Lore

Job classes have their own preferred weapons but thanks to Weapon / Equipment Lore skills, you can equip a weapon to a job that's not good in handling it. Lores instantly raises the character's aptitude towards a particular weapon, armor, helm or shield to rank S. Most lores are also learned quite early since the job level required to unlock them is quite low. These useful abilities allow you to equip weapons to incompatible jobs and enjoy the weapon aptitude bonus at the same time.

Shield Lore is a very useful for magician or support-type classes like white mages, spiritmasters, arcanists, black mages, etc. This allows them to equip a shield on their free hand (or two shields if you have the Knight's Dual Shield ability) and enjoy its full protection. This is quite beneficial since these jobs don't need to increase their physical attack power through Dual Wield or Two-Handed.

Armor and Helms provide the best defense ratings and only a handful of classes have good aptitude towards them. These Templar and Dark Knight support abilities can turn a different job to a tank at a cost of a few support ability slots.

Equipment Lore Jobs