Unarmed Fighting Master

Ability Score Increase: Increase your Strength or Dexterity Score by 1, to a maximum of 20.
Unarmed Strike Mastery: When you hit a creature with an Unarmed Strike as part of the Attack Action on your turn, you can cause the strike to deal extra damage to the target. The extra damage equals your Proficiency Bonus.
Haymaker: Before you make a melee attack with an Unarmed Strike, you can choose to take a -5 penalty to the attack roll. If the attack hits, you add +10 to the attack's damage.
Hew: Immediately after you score a Critical Hit with an Unarmed Strike or reduce a creature to 0 Hit Points with one, you can make one more Unarmed Strike as a bonus action.