Elemental Affinity

Elemental Affinity is a trait present in some pieces of equipment in the series, which enhances the elemental damage dealt by the user.

Final Fantasy V
Several pieces of equipment in the game increase the power of elemental attacks by +50%.

The bonus is applied before subtracting the opponent's Magic Defense.

Final Fantasy XII
When a character equips a weapon or armor that has an elemental affinity, all damage, both physical and magickal, associated with the element, is boosted by 50%. The affinity bonus is independent of the weapon's own element, in that the bonus usually exists on its own and elemental weapons usually don't have an elemental affinity. For example, none of the staves that have the elemental affinity trait have an element in the weapon -- the user benefits from the affinity by casting magick of the element the weapon gives a bonus for, but there is no bonus for physically attacking with said weapon as the damage with physical attacks is non-elemental. All ninja swords have the element of Dark, but none have an elemental affinity on the Dark element. In order to apply the elemental affinity to ninja swords, the character must wear the Black Robe armor, which gives a +50% boost to Dark elemental damage, making all attacks dealt with ninja swords +50% the normal damage.

Holy Rod is the only weapon that is both elemental and has an elemental affinity; its Holy element is strengthened by its Holy affinity, so all physical attacks will be 50% more powerful, compensating for the weapon's fairly low attack power. The effect is even greater against enemies that are weak against Holy, as they will take double damage from Holy, plus the +50% bonus. Potentially the greatest damage increase is dealt with the Flame Staff or Burning Bow against an oiled opponent, as oiled targets take triple the normal damage from Fire-elemental attacks. Elemental affinities do not stack, so there is no benefit in equipping two pieces of equipment that give an affinity to the same element simultaneously.