Raises Defense occasionally.Description
Gamble Defense, also known as Gamble Defence in the European English version, is a support ability in Final Fantasy IX for Zidane, Freya, Quina, and Amarant that makes the wearer's Defense random when physically attacked; contrary to what the in-game flavor text says, Defense can be lower than the base stat as well as higher. Due to the diminishing returns of a high Defense stat in damage calculation, Gamble Defense is a detriment rather than a boon and should not be equipped. Gamble Defense costs just one Magic Stone to activate.
Gamble Defense is learned from Twist Headband, Adaman Hat, Power Vest, and Barette for variable amounts of AP; Zidane and Freya learn it the fastest at 20 AP, while Quina learns it the slowest at 40 AP. Equipping multiple pieces of equipment that all teach the same ability, learns the ability faster.
Barette is the one piece of equipment that everyone can learn it from, synthesized in Lindblum and other towns after the Battle of Lindblum, and also found in Ipsen's Castle. It is also an exceedingly rare (1/1024) treasure in Chocobo Hot and Cold.
Twist Headband for Zidane, Quina, and Amarant is bought from shops after the party returns from the Outer Continent. Power Vest for the same characters is found in Oeilvert and stolen from the boss there, and Adaman Hat for the same characters is later bought from Bran Bal and Daguerreo after visiting Bran Bal.
When Gamble Defense is active, whenever the character receives physical damage, the damage is calculated against a randomly generated Defense stat that can range from 0 to double the character's Defense stat. This works against the player's favor, as part of the damage calculation, the enemy's Attack is compared against the player character's Defense, and the best result is when the party member's Defense stat matches or eclipses the enemy's Attack stat. The amount Defense eclipses Attack does not matter; the enemy will never do just 0 damage no matter how high the character's Defense. This means that reduced Defense will always have an impact to damage received, whereas the positive effect of Gamble Defense diminishes the higher the character's base Defense is. In other words, as soon as the character's Defense stat reaches half the enemy's Attack stat, the benefits drop off.
Gamble Defense does nothing against magic damage.
Gamble Defense should not be equipped, as the party member will take more damage on average than without it. It would couple poorly with Cover or Protect Girls as well. To protect against physical damage, the party can instead equip Distract. Other methods to mitigating damage are Vanish or Protect or Freya's Jump, and avoiding armor that are falling behind stats-wise.