Steadfast Determination (3.5e Feat)
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Steadfast Determination [Combat]
Your physical durability allows you to shrug off attacks that would cripple a lesser person. Rather than depend on agility or willpower, you use your raw toughness to survive, you hunker yourself down prepping yourself the mental assualt with sheer force of constitution.
Prerequisite: Toughness, Iron Will
Benefit: If you are forced to attempt a Will saving throw, you can use an immediate action to add your con mod to your Will saving throw. Whether the saving throw is successful or not, you are unable to move till the end of your next turn. If you are prevented from becoming immobile, you can’t use Steadfast Determination, nor can you ignore the immobile condition from Steadfast Determination or remove it early.