| Type | Icon | Name | SP | Required | Description |
|---|---|---|---|---|---|
| A | 
|
Fort. Def/Res 1 | 100 | Fortress Def 1,Fortress Res 1 | Grants Def/Res+3. Inflicts Atk-3. |
|
Fort. Def/Res 2 | 200 | Fort. Def/Res 1 | Grants Def/Res+4. Inflicts Atk-3. | |
|
Fort. Def/Res 3 | 300 | Fort. Def/Res 2 | Grants Def/Res+6. Inflicts Atk-2. | |
| No restrictions. | |||||
Available as a Sacred Seal.
List of owners
| Unit | Skill chain | |||
|---|---|---|---|---|
 | Fortress Def 1 5  | Fort. Def/Res 1 5 | Fort. Def/Res 2 5 | Fort. Def/Res 3 5 |
 | Fortress Def 1 5 | Fort. Def/Res 1 5 | Fort. Def/Res 2 5 | Fort. Def/Res 3 5 |
 | Fortress Def 1 5 | Fort. Def/Res 1 5 | Fort. Def/Res 2 5 | Fort. Def/Res 3 5 |
 | Fortress Res 1 5 | Fort. Def/Res 1 5 | Fort. Def/Res 2 5 | Fort. Def/Res 3 5 |
 | Fortress Def 1 4  | Fort. Def/Res 1 4 | Fort. Def/Res 2 4 | – |
 | Fortress Res 1 3  | Fort. Def/Res 1 4 | Fort. Def/Res 2 5 | – |
Gallery
The erroneous icon used for Fort. Def/Res 1 when it was initially released. It was later removed when all ranks of the skill borders were upgraded.
In other languages
| Language | Name |
|---|---|
| English (US) | Fort. Def/Res |
| Japanese | 守備魔防の城塞 |
| German | Ver./Res.-Fest. |
| Spanish (Europe) | Bastión Def/Res |
| Spanish (Latin America) | Fort. Def./Res. |
| French | Fort. Déf/Rés |
| Italian | Forte Dif/Res |
| Traditional Chinese (Taiwan) | 防守魔防堡壘 |
| Portuguese | Fort. Def./Res. |