Great Weapon Master

4th Level Feat, Proficiency with Any Martial Weapon

Repeatable: No   You’ve learned to use the weight of a weapon to your advantage, letting its momentum empower your strikes. You gain the following benefits:   Ability Score Increase. Increase your Strength score by 1, to a maximum of 20.
Cleave. Immediately after you score a Critical Hit with a Melee Weapon or reduce a creature to 0 Hit Points with one, you can make one attack with the same weapon as a Bonus Action.
Heavy Weapon Mastery. When you hit a creature with a Heavy Weapon as part of the Attack Action on your turn, you can cause the weapon to deal extra damage to the target. The extra damage equals your Proficiency Bonus, and you can deal it only once per turn.