Determined Soul, Variant by Aarnott (3.5e Feat)
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 Determined Soul [General]
Through your will alone, you can increase your resilience.
Prerequisite: Iron Will
Benefit: You may add the higher value of either your Constitution bonus or Wisdom bonus to each Hit Die when determining your hitpoints. If one of the ability scores gets a higher modifier than the one currently used for calculating your hitpoints, recalculate your hitpoints.
Normal: You add your Constitution bonus to each Hit Die when determining your hitpoints.