Adepts that pursue an inward path to enlightenment and perfection discover that the soul can be a gateway to the apotheosis they seek, the tether upon which their life depends becoming a means to reach incredible heights. These warriors do not just consider concepts of life and death, but foster the power of their souls to walk between the realms of mortality while they still yet live and breathe.
Beginning at 3rd level when you choose this archetype, you can use a bonus action and spend 3 exertion to turn your arms partially incorporeal for a number of rounds equal to your Wisdom modifier. You can make your arms corporeal again by using a bonus action or your reaction.
While your arms are partially incorporeal, you add a second martial arts die to damage dealt by your unarmed strikes as your blows disrupt your target internally. You can also use this partial incorporeality to use an action to reach through an object and interact with what is just on the other side, such as a door handle, window latch, or item. You cannot use this ability to pass through metal objects or surfaces. However, when you do this, you take 5 (1d10) force damage every round you remain in the object. If this feature’s duration ends while you are inside an object, you take 10 (2d10) damage as your arms are ejected.
At 6th level, you learn how to land a blow while manipulating your corporeality. As part of your Attack action, you can spend 1 exertion to deal force damage with your unarmed strikes and melee weapon attacks until the start of your next turn.
Starting at 11th level, you learn how to make your entire body as insubstantial as a spirit’s. You can use an action and spend 5 exertion to become incorporeal for up to a number of rounds equal to your Wisdom modifier. You can also end this effect by using a bonus action or your reaction. While incorporeal, you can still be seen as a faded version of yourself, but you gain advantage on all Stealth checks, resistance to all types of damage except force damage, and may pass through objects and creatures as if they were difficult terrain .
You take 10 (2d10) force damage if you end your turn inside an object. If you end your turn in a space occupied by a creature, it must roll a Dexterity saving throw against your Maneuver DC, avoiding you on a success. On a failure, you both take damage equal to your martial arts die × your Wisdom modifier. If this feature’s duration ends while you are inside either an object or a creature, you take 10 (2d10) points of force are shunted to the nearest open square and take an additional 5 (1d10) points of force damage for every square moved.
At 17th level, you are able to move through the world as lightly as the ghosts you emulate. You gain a fly speed equal to half your Speed and the ability to hover, and also gain an expertise die on all Acrobatics and Stealth rolls. You are also immune to the poisoned condition.