Your mind is a fortress, of which not much can infiltrate or afflict harm to. As an Active Semblance, Iron-willed grants the user a few unique abilities, all of which are passive.
Passively, you gain resistance to psychic damage and gain an advantage on all Wisdom, Intelligent, and Constitution Saving Throws, and this applies to Concentration checks too.
Actively, you can spend 1 aura charge to use the action, Determination, fully nullify any effect on your mind, such as charmed, frightened, or other mental effects, such as mind control. This also allows you to ignore trauma/pain along with remaining focused, granting you the ability to also spend 1 charge to keep your concentration up.
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