Oh, shut up and help me remodel the Vitality (stat) page!
Vitality (たいりょく, Tairyoku?, lit. Physical Strength), usually abbreviated as VIT, is a defensive statistic. In games where it is present, a creature's vitality is either compared versus Strength to help determine damage or is used to determine HP. Vitality is often modified by equipment.
Vitality is one of the five base stats and determines how much HP a character gains when they level up.
Vitality determines how much HP is gained during level up and is determined by the current job.
In the original, on a normal level up, a character gains (VIT/4)+1 Max HP. On a strong level up, they gain 20+(VIT/4)+R Max HP, where R is a random number from one to six inclusive. Vitality also gives a boost to defense.
In the remakes, the HP gain formula is:
Level + Vitality + (Vitality × Random(1 to 1.5))
Vitality affects the amount of damage taken from physical attacks. It can be increased with the Guard Source item.
Vitality affects the amount of damage taken from physical attacks. It may also be increased by equipping the appropriate Materia.
The VIT statistic determines how much damage is taken from physical attacks. This statistic can be increased through the Junction system. Both playable characters and enemy's VIT statistic can be nulled if the Vit 0 status is incurred.
Vitality is a stat that is compared with an attacker's Strength to determine the damage curve and reduces the maximum amount of damage that a character takes from a blow. Tanks, primarily Paladins, raise VIT in order to live longer and make a White Mage's job easier. For every two points of Vitality, a character's Defense stat is raised by one point. VIT further affects how much HP is restored from curative spells.
It is associated with the Earth element, and thus many Earth-based items add VIT to a player's stats.
Vitality is the rate of resistance from negative status effects and the length of status effects (including positive ones). Essentially, Vitality makes beneficial statuses last longer (up to 99% extra) and harmful statuses last shorter (up to 49.5% reduction). Vitality also helps determine damage of axes, hammers, and hand-bombs.
Many bosses have the Ignore Vitality passive ability, which means their statuses will always hit unless the target is immune (although under Shell the chance is still halved). The player can replicate the effect by equipping the Indigo Pendant accessory.
The accuracy underflow bug is a glitch in some versions of Final Fantasy XII where, when a low level character with extremely low Magick attempts to use a status move on a target with very high Vitality, the accuracy can underflow, guaranteeing the success rate.
Vitality, along with Defense, affects the damage received by physical attacks. This damage can be modified by equipping certain accessories, along with purchasing Vitality Level from the Ascension Grid.
According to the in-game Help menu, Vitality "affects physical damage taken."