Masks have been used since the dawn of time to not only conceal one's face, but to become another person entirely. It would seem this black mask was made with black mages in mind, as it raises the wearer's DEF and MAG, while also providing resistance against the dark element. Rumor has it that an identical mask in white exists in another part of this world.
Black Mask is a recurring piece of equipment in the series. It has appeared as a hat, head armor, and an accessory.
In the original version, Black Mask is mystic head armor that provides 53 Magick Resistance, absorbs Dark, and Magick Power +8. It requires the Mystic Armor 10 license to equip. It can be bought from Balfonheim Port for 12400 gil, from the Black Vestments bazaar set, found as a treasure in Great Crystal (Kabonii Jilaam Pratii'vaa), or dropped from Banshee (1%).
In the Zodiac versions, Black Mask provides 53 Magick Resistance, +81 MP, +8 Magick Power, absorbs Dark. It requires the Mystic Armor 10 license to equip. It can be found as a treasure in Cerobi Steppe (The Terraced Bank) and Pharos - First Ascent (Horizon's Cusp), dropped by Banshee (1%), stolen from Piscodaemon (3%) in Trial Mode Stage 55 and Zodiark (55%) in Trial Mode Stage 97, created and bought from the Black Vestments bazaar set for 12,800 gil, or from the Hunt Club sidequest.
Mask that shines black in the moonless night.
Black Mask is an accessory with the Pinpoint ability which increases duration of fletch abilities. It can be found as a treasure from Mission 8-2C.
Black Mask is a helmet.
Black Mask is a hat that provides 12 DEF, 18 MAG, and +15% Dark resistance. It can be found during the exploration of Inside Labor Camp and obtained as the reward for completing the mission "Warrior of Earth and Sea".