Monk that focuses on pure brutality of a brawler

Brutality

Starting at 3rd level, you’re able to strike with your unarmed attack with brutal force. Whenever you hit with an unarmed strike or a monk weapon, you roll one additional martial arts die as extra damage. Once per turn anytime when you successfully make an Unarmed attack, you may spend a Ki Point and impose one of the following effects on that target:

• It must succeed on a Dexterity saving throw or be knocked prone.
• It must make a Strength saving throw. If it fails, you can push it up to 15 feet away from you.
• It can’t take reactions until the end of your next turn.

Brawler

If a target makes a melee attack against you, after that attack resolves you may immediately use a reaction to make an attack of opportunity against the melee creature that attacked you.

Body of the Brute

At 6th level, you can use a reaction to reduce damage taken by 1D10 + Con + Monk Level. If the damage was from a melee attack against you and you reduced the damage to 0, you may immediately use a Ki point as apart of the same action to make an attack of opportunity against the melee creature that attacked you.

Brutal Fist

Beginning at 10h level, When one of your unarmed attack or monk weapon hits a target, You may Spend 2 Ki points to Double the damage dealt by that attack. This applies after the damage is calculated.

Quivering Fist

At 17th level, you gain the ability to set up lethal vibrations in someone’s body. When you hit a creature with an unarmed strike, you can spend 3 ki points to start these imperceptible vibrations, which last for a number of days equal to your monk level. The vibrations are harmless unless you use your action to end them. To do so, you and the target must be on the same plane of existence. When you use this action, the creature must make a Constitution saving throw. If it fails, it is reduced to 0 hit points. If it succeeds, it takes 10d10 necrotic damage.

You can have only one creature under the effect of this feature at a time. You can choose to end the vibrations harmlessly without using an action.