Auto-Reflect

Auto Reflect is a recurring ability that permanently puts the user in Reflect status. This guarantees that the majority of spells cannot harm the user, but also means that the user cannot benefit from positive spells or even be cured by healing spells, up to the point that they cannot be revived with the Life spells. The effects of Auto Reflect cannot be dispelled either. It is usually granted by the accessory Reflect Ring.

Final Fantasy V
The Reflect Ring (Wall Ring in earlier versions) enables this ability, and can be equipped by anyone. It does not grant any stat bonuses. It can be found in Istory Falls, can be won (rarely) from Reflect Knight and Serpentina, and is a common win from Leviathan. In addition, it's a common steal from Disablers, Furies, and Carbuncle, and is a rare steal from Reflect Mage, Wood Sprite, and Barrier. The enemy Carbuncle has Auto-Reflect as well.

Final Fantasy VI
The Reflect Ring (Wall Ring in the SNES version) enables this ability, and can be equipped by anyone. It can be found in Narshe and the Imperial Camp in the World of Balance, and can also be won from the Colosseum by betting an Elixir. It can also be bought in the World of Balance in Albrook and Thamasa, and in the World of Ruin in Narshe and South Figaro.

Final Fantasy VII
The Reflect Ring enables this ability, and can be equipped by anyone. It is first acquired after defeating Jenova DEATH, and can later be stolen from Ultimate Weapon while chasing it around the world, and while it's on the ground.

Final Fantasy VIII
Auto-Reflect is an ability that can be learned on the GF Carbuncle for 150 AP or by using a Glow Curtain item on any GF.

Final Fantasy IX
The Reflect Ring is an Add-on that teaches the ability, and can be equipped by anyone. It is acquired by either buying it at the Treno Auction House or synthesizing an Anklet and a Madain's Ring for it on Disc 4 in either Black Mage Village, Alexandria, Treno, or Lindblum. It doubles the damage taken from Fire, Ice, and Lightning elemental attacks, and increases Strength, Magic, and Magic Defense by +1. It also teaches the abilities Reflect and Distract.

Final Fantasy X
Auto-Reflect is a customizable ability by customizing 40 Star Curtain onto an armor.

Final Fantasy X-2
Auto-Reflect is an ability that can only be used on the Shining Mirror Garment Grid by passing through the red gate, or by equipping the Star Bracer.