Having lived so long in the hostile wastes, you are adept at survival, be that combat or otherwise.

Always dangerous.

At 3rd level, you take precautions  to always be ready for combat and always have a weapon to fight with.

When you pick up an improvised weapon, you can make that weapon your dedicated weapon until the end of your next short or long rest . You can only make an improvised weapon your dedicated weapon once per short rest, unless you spend a ki point to do it again. Once per turn, when you make an attack with that weapon, you add your dexterity modifier twice to  damage rolls with that weapon. Your dm defines that weapons statistics while you are wielding it as normal.

When you hit an enemy with an attack, you spend two ki points to make an attempt to disarm that target, if you succeed you may also pick up that weapon as part of that same reaction. if that weapon requires attunement, you can make a survival check against that weapon's attunement dc (8 + the previous wielder's proficiency bonus + that wielder's wisdom), and if you succeed you become attuned to that weapon until the end of your next turn, where you have to make another check, and if you succeed you continue to be attuned to that weapon but if you fail you drop the weapon and it is no longer attuned to you. Repeat this check at the end of each of your turns.

Perseverance of the survivor.

At 6th level, you gain the ability to persever in the face of death.

You have advantage on repeat saving throws to end a condition on yourself, in addition, any negative effect afflicted on you by an enemy has its duration halved as long as it lasts a minute or longer, such as spells like "Hold Person" and "Hypnotic Pattern", or effects like the poisoned or frightened conditions.

Desperate critical.

Beginning at 11th level, While you are wielding an improvised weapon that is your dedicated weapon, on any attack after the third you make with that weapon in a turn you can choose to break that weapon, and if you do that attack becomes a critical hit. you lose that weapon and it cannot be wielded by anyone. when you break the weapon,  you can spend a ki point to pick up another improvised weapon to use as your dedicated weapon within reach. if there is nothing to use or choose not to pick one up, you may instead move up to half your movement without provoking an attack of oppertunity. 

you can on'y use this feature a number of times equal to your wisdom modifier.

In addition, your improvised weapon attacks count as magical.

Surviving Soul.

At 17th level,  once per turn round you make an attack with an improvised weapon, you may add your wisdom modifier to the attack and damage roll. In addition you double your proficieny bonus when you make a survival check, as long as you have no other bonuses doubling your proficiency bonus to your survival checks. While you are wielding an improvised weapon or weapon taken from a disarmed opponent, you may make an additional attack as part of your attack action. Additionaly if you get hit by an attack that would reduce you to zero hitpoints,  you may break your improvised weapon and spend 2 ki points instead, then regain hitpoints equal to one roll of your martial arts die + your wisdom modifier (you take no damage from that attack). You can only do this once per round.