Aura Seal

Aura Seal is a debuff in Xenoblade Chronicles and Future Connected. It prevents the victim from using any arts that are s, in addition to neutralizing any s the foe might possess for the duration. It does not naturally erase any active auras, though the only art that inflicts Aura Seal is, which does also clear auras.

Aura Seal is a situational debuff. It is useless against enemies that do not possess auras or spikes, but against those that do, it can be the one thing that saves the battle against them.

Aura Seal does not prevent an aura from activating if the enemy has already begun using its art. As a result, it is presumed that the debuff's effect is to simply prevent the victim from being able to initiate an aura art, as it clearly doesn't actively block the aura's creation in the same way that Debuff Immunity does. As there are no enemies that can apply the debuff on the party, there is no way to be sure.