Shell activates automatically in battle.
Auto-Shell (オートシェル, Ōto Sheru?) is a recurring ability that maintains a constant Shell status on the user. It is usually non-dispellable and will not wear off even if the user is knocked out and revived in the same battle.
Auto-Shell is found on the relic Guard Bracelet. The Force Shield gives out a permanent Shell status, but only when equipped before battle. Enemies that has the Shell status innately cannot be removed by Dispel, and as such, it is permanent. Gau and Gogo under the Rage status can gain this ability permanently when using specific Rages.
Auto-Shell is learned on the GF Doomtrain for 250 AP. It can also be taught to any GF by the item Moon Curtain. Moon Curtain can be refined from 20 Magic Armlets or 100 Malboro Tentacles with Eden's GFAbl Med-RF ability.
Auto-Shell is an auto-ability. It can be found on dropped armor or customized onto armor by using 80 Lunar Curtain items. Characters with the equipped armor will permanently have the Shell status. It cannot be removed with Dispel.
Auto-Shell is an ability found on the Mascot dressphere, and requires 80 AP to learn. The ability can also be accessed via the accessory Moon Bracer and by passing through the red gate on the Selene Guard Garment Grid.
The Shell Shield bestows an automatic Shell effect. It is a Hunt reward for the Wyvern Lord and can also be found in the secret passage in Stilshrine of Miriam. In the Ward of the Sword-King there is a junction: the path to the left has a wall that will vanish if the player approaches it in a way the camera will attempt to go "inside" the wall. Shell Shield can also be found in a randomly spawning treasure in Cerobi Steppe and Tchita Uplands' Highlands, but the chance of it spawning is low.