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Ironhide Resilience
Type of Feat: general (available every three level-ups)
Prerequisite: Dex 13+, Con 13+, barbarian 3
Specifics: Allows you to use your constitution modifier in addition to your dexterity modifier for AC if using no armor. To a maximum of your level.
Use: automatic.
Important Note: This is not like Monk AC, allowing you to use a shield and items that include damage immunity, unlike the bonus AC provided to monks with Monk AC Bonus or Blessed be the Vestments