ST-Def is a junction that your characters can gain access to if they have Guardian Force that has the 
ST-Def-J junction ability. There are additional junctions including ST-Def-Jx2 or ST-Def-Jx4 abilities that allow you to protect your characters against a multitude of status effects. Some provide 100% protection for a single status, while others offer partial protection to many statuses.
“ST-Def signifies status defense, either already in use, or actually setting a status to defense. This defends against certain status changes. If attacked by Petrify while the defense is set against Petrify, a status change doesn’t occur.”
- In Game Online Help Section
The list of magic below indicates which statuses you can protect against:
| Magic | Status Resisted |
|---|---|
 Aura |
100% chance to resist  Curse status. |
| Berserk |
100% chance to resist  Berserk status. |
| Bio |
100% chance to resist  Poison status. |
| Blind |
100% chance to resist  Blind status. |
| Break |
100% chance to resist  Petrify status. |
| Confuse |
100% chance to resist  Confuse status. |
| Death |
100% chance to resist  Death status. |
| Death |
50% chance to resist  Drain status. |
| Drain |
100% chance to resist Drain status. |
| Esuna |
20% chance to resist Berserk status. 20% chance to resist Blind status.20% chance to resist Confuse status.20% chance to resist Curse status.20% chance to resist Petrify status.20% chance to resist Poison status.20% chance to resist  Silence status.20% chance to resist  Sleep status.20% chance to resist  Slow status.20% chance to resist  Stop status. |
| Full-Life |
40% chance to resist Death status. |
| Holy |
40% chance to resist Berserk status. 40% chance to resist Confuse status.40% chance to resist Curse status.40% chance to resist Death status.40% chance to resist Drain status.40% chance to resist Poison status.40% chance to resist Sleep status.40% chance to resist  Zombie status. |
| Life |
20% chance to resist Death status. |
| Pain |
100% chance to resist Darkness status. 100% chance to resist Poison status.100% chance to resist Silence status. |
| Quake |
100% chance to resist Stop status. |
| Reflect |
40% chance to resist Berserk status. 40% chance to resist Blind status.40% chance to resist Confuse status.40% chance to resist Petrify status.40% chance to resist Poison status.40% chance to resist Silence status.40% chance to resist Sleep status.40% chance to resist Slow status.40% chance to resist Stop status. |
| Silence |
100% chance to resist Silence status. |
| Sleep |
100% chance to resist Sleep status. |
| Slow |
100% chance to resist Slow status. |
| Zombie |
100% chance to resist Zombie status. |