Way of the Iron Fist

Similar the the open Hand tradition, the Iron Fist excel at hand to hand combat. The style descends from an orc who used ki to operate an iron gauntlet in place of his hand which had been cut off. 

Iron Grip

Starting at 3rd level, When you are attacked by a melee weapon you can use a reaction to deflect or grab an opponents weapon if you main hand is free. When you do so the damage is reduced by 1d10 + str modifier + your monk level, if reduced to zero you get an attack of opportunity.

Wholeness of Body

At 6th level, you gain the ability to heal yourself. As an action, you can regain hit points equal to three times your monk level. You must finish a long rest before you can use this feature again.

Tranquility

Beginning at 11th level, you can enter a special meditation that surrounds you with an aura of peace. At the end of a long rest, you gain the effect of a Sanctuary spell that lasts until the start of your next long rest (the spell can end early as normal). The saving throw DC for the spell equals 8 + your Wisdom modifier + your proficiency bonus.

 

Iron Fist Strike

Upon reaching 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.