Heavy Armor Master Feat 5e
Source: Player’s Handbook
Prerequisite: Proficiency with heavy armor
You can use your armor to deflect strikes that would kill others. You gain the following benefits:
Increase your Strength score by 1, to a maximum of 20.
While you are wearing heavy armor, bludgeoning, piercing, and slashing damage that you take from nonmagical attacks is reduced by 3.