Defiant [Erenlander]

Prerequisites: Erenlander.

Benefit: When you fail a Fortitude or Will saving throw against something that will have some negative or incapacitating effect on you other than hit point damage (such as an enchantment effect, fear effect, sickening effect, or poison), you may ignore the negative effects of the attack for long enough to perform a single round's worth of actions. As soon as your turn is finished, however, you are subjected to the effect, but it has become even stronger. If it inflicted numerical penalties to ability scores, checks, attack rolls, or the like, those penalties are doubled. If the attack has some non-numerical effect, such as causing you to become dominated or panicked, the duration of the effect instead doubles. Either the numerical penalties or the duration are doubled, but not both. The DM is the final arbiter of which occurs.

This feat does not stave off the effects of an attack that instantly kills you, such as a death effect.

Normal: The effects of an attack occur immediately upon the failure of the saving throw.

Source: Destiny and Shadow, p. 56