Monks of the Way of the Closed Hand believe that the best way to settle a dispute is a fist to the mouth. No more need be said, except that they have a peculiar hatred for monks who follow the Way of the Open Hand. Nobody knows why.

Powerful fists

Beginning at 3rd level, you are capable of making your fists more powerful. When you hit a creature with an attack from your flurry of blows feature, you can cause the attack to deal double damage. You can use this feature a number of times up to your Strength modifier (minimum of 1). You regain all expended uses when you finish a long rest.

Rigid grip

Starting at 6th level, your grip becomes significantly tighter. You cannot be disarmed of a weapon you are holding, and you have advantage on checks made to grapple an opponent, as well as other checks that require a tight grasp. For checks that only have a partial element of grasping (such as climbing a rock face with slippery handholds) you instead have a +2 bonus to the check, and cannot have disadvantage on it.

Nimble fists

From 11th level, your fists require less strength and more agility and dexterity. You can make ability checks that your rigid grip feature applies to using your Dexterity modifier instead of any other modifier. In addition, the ability granted by your powerful fists feature can be used a number of times up to your Dexterity or Strength modifier (your choice) before a long rest.

Knockout blow

Beginning at 17th level, you gain the ability to land a single devastating blow, exhausting yourself but destroying enemies. As an bonus action on your turn, when you make an unarmed strike, you can choose to increase your exhaustion level by up to 3. For each level of exhaustion you gain, the blow deals an additional 3d10 bludgeoning damage and 1d12 psychic damage. There is no limit to using this ability, but if you increase your exhaustion level to 6 through it, you die as usual.