Charismatic Defense (5e Class Feature)
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Paladin/Warlock/Sorcerer class feature
This variant class feature can be taken by any class with proficiency with light, medium and/or heavy armor. This class feature replaces all of the class's armor proficiencies, except for shield proficiency.
Your overwhelming magical power makes you a hard target to hit. While you are not wearing any armor, your Armor Class equals 10 + your Charisma modifier + your Constitution modifier. You can use a shield and still gain this benefit.