Those who deem it their destiny to train their bodies, minds and souls to protect others and achieve a transcendent state of being can take many forms. Among them, there is a group that chooses differently from the rest. Instead of empowering their attacks or attuning to the different aspects of the world around them, this group chooses to strengthen their physical forms, realizing that only through them can they interact with the world around them. They empower the Ethereal to better withstand the assault of the Material, all the while engaging in a physical training regimen that grants them superior resilience when combined with meditation and peace of mind.

The First Of The Iron Flesh

Around the time of the genesis of martial arts studies lived a great warrior. This woman stood apart from others who followed the same path, not due to her strength or her superior fighting skills, but due to the incredible amount of physical punishment she could endure, usually resulting in a victory of attrition for her whenever she sparred with the others. Her name was Zao Xiei.
Whenever she took to the battlefield she stood her ground in much the same way, weathering blows from all sorts of foes and weapons. At the end of those battles she emerged bruised but only lightly wounded. Some claim they saw her block greatswords mid-swing with one hand and stop spears with her body, leaving behind only the smallest of marks on her skin. One particularly strange report said that she stood before a horse in full gallop and stopped it in it's tracks with her bare hands.
As the years went on, stories grew larger and more questionable, but the guiding principles of Zao Xiei's teachings remained preserved through the ages and available to those of a will strong enough to follow in her footsteps.

Forging Iron Souls

Those who wish to become practitioners of the Way Of The Iron Flesh are forewarned of it's difficulties. The physical training is more intense, the studies of the world are longer and more comprehensive and the spiritual trials that one must go through to achieve the level of enlightenment required to succeed are enough to break those of lesser will.
The Way Of The Iron Flesh teaches that if the spirit stands strong, so too can the vessel which carries it. To become a practitioner of the Way Of The Iron Flesh is no small feat. To excel in it is a badge worn only by the greatest masters. The students of this path have dubbed the process they go through as The Forge.
With the Iron Flesh a monk can withstand all manner of physical assault all while maintaining a calmness of spirit that allows them to shrug off ailments of the mind that others would struggle with. Following this Way allows one to become a true defensive force that can take the blows, as well as evade them.

 

Training Of The Mind

Your body and mind must be trained in equal measure to achieve a greater understanding of the Way Of The Iron Flesh. Your theoretical studies make you more adept at different branches of knowledge.

At 3rd level, you gain proficiency in 2 skills of your choice that use Wisdom or Intelligence.

Iron Body

Starting when you choose this tradition at 3rd level, you gain a hightened form of physical defense, reflected by your hardened training regimen. Your Unarmored Defense changes from 10 + your Dexterity modifier + your Wisdom modifier to 13 + your Dexterity modifier+ your Wisdom modifier.

You also develop the ability to increase your defensive power even further in a split second, by using your Ki to harden your body in the localized areas of your enemies atttacks. You can spend 1 Ki point, as a reaction, to increase your AC by a value equal to your Wisdom Modifier. This lasts until the beginning of your next turn.

Will Of The Forge

At 6th level, you become even more formidable against attacks to your mind and spirit. In this process you also make yourself more adept at seeing the things that do not wish to be seen and to intuit with greater clarity on any and all situations.

Everytime you are forced to roll a Wisdom Saving Throw, you get to do so with advantage. Everytime you make an ability check that involves the use of your Wisdom you get to double your proficiency bonus.

Strike The Iron While It's Hot

Beginning at 11th level, you can take the pain inflicted upon you and use it to strike a single target into submission. As an action you can spend 2 Ki points to make a melee attack against one creature. This attack  is done with advantage. If you hit, roll your normal damage for the attack and add half the damage you suffered between your last turn and the current one + your Wisdom Modifier to the damage roll. This actions counts as you taking the attack action.

Zao Xiei's Iron Stance

At 17th level, you learn the ultimate secret of the Way Of The Iron Flesh: Zao Xiei's Iron Stance technique. With it you can call attention to yourself while simultaneously making yourself completely immune to most forms of damage for a short time. It does cause an extreme strain on the body and the spirit however, making it that much clearer that this is a last resort. When all else falls, you will not.

As a reaction, you can become immune to all damage except necrotic, radiant or psychic. You don't need to roll saving throws against anything unless the damage type you are saving against is necrotic, radiant or psychic. You are immune against all conditions. Any enemy within 30 ft. of you, that tries to attack a creature other than you, must do so at disadvantage. This effect lasts until the start of your next turn. You can do this once per long rest and after using this ability you suffer a point of exhaustion.