Jsk Feats:Heavy Weapon Master

You've learned to deliver crushing blows using mighty weapons. You gain the following benefits:
 * While you are wielding a heavy weapon in both hands, you gain a +1 bonus to your AC against attacks made within 5 feet of you.
 * Grounded Attack: When you make a weapon Attack with a heavy weapon, you can choose to reduce your speed for the turn to gain a bonus to your attack roll. For every 10 feet you reduce your speed, you gain a +1 bonus to your attack roll, to a maximum bonus of +5. If you make an Attack with a bonus of at least +3, you score a critical hit on a roll of 19 and 20. If you make an Attack with a +5 bonus, you score a critical hit on a roll of 18, 19, and 20 (see the Grounded Attack Table below).
 * Heavy Attack: If you score a critical hit with a heavy weapon, the target of that attack must make a Strength saving throw against a DC equal to 8 + your proficiency bonus + your Strength or Dexterity modifier (your choice). On a failed save, the creature is knocked prone and takes additional damage equal to your Strength modifier (a minimum of 0).
 * Power Attack: When you make a weapon Attack with a heavy weapon and you have advantage on the attack roll, you can choose to forgo your advantage and gain a +3 bonus to your attack roll instead. This bonus is additive to the bonus granted by your Grounded Attack. If you score a critical hit with a Power Attack, the creature does not make a saving throw against being knocked prone (see the Heavy Attack ability). Instead, the creature must succeed on a Constitution saving throw or take additional damage equal to your Strength modifier (a minimum of 0) and be stunned until the end of its next turn.