A rare high-ranking hat with high defense.
The Glass Mask is the most powerful hat in terms of defense, providing +30 Defense and -10 Evasion in the 2D versions. It can be dropped from Deathmask or Proto Deathmask. In 2D versions, it is capable of being equipped by any character. In the 3D version, it can only be equipped by Cecil, Kain, Rydia, Rosa, and Edge.
The Glass Mask is one of the more powerful helmets, providing +30 Defense and -10% Evasion, and equippable by all characters. It still boasts the highest defense of any helmet, although its magic defense is still lacking. It can only be dropped from Proto Deathmask (very rare).
The Glass Mask is a level 90 hat that provides +290 Bravery as well as BRV Boost on Dodge +2%. It can be obtained from the shop by trading 79,000 gil, Tiger Mask, Shiva's Veil, and Wanderer's Dream x5.
Glass Mask is a hat that provides 35 DEF. It is obtained from the Final Fantasy IV event, "The Tower of Zot".