Tavern Brawler is a passive feature obtainable by the Feat of the same name. Users of this feature excel at improvised and unarmed fighting and deal more damage more often.
Description
Increase your 
Strength or 
Constitution by 1, to a maximum of 20.
When you make an unarmed attack, use an improvised weapon, or throw something, your Strength Modifier is added twice to the damage and 
Attack rolls.[See: Bugs]
How to learn
Granted by feats: Tavern Brawler (Feat)
Bugs
- As of Hotfix 6, the bonus Strength modifier damage from throws with Tavern Brawler seems to be directly applied to objects, bypassing any Toughness condition they may have. Thus, even if a character cannot deal enough normal damage in a single attack, they can still slowly but surely chip down the health of any locked door or chest by repeatedly throwing an item.