A blind master has mastered the art of fighting while blindfolded.They rely on there ki amplified ears to see where things are. The monks that teach in this art believe if you’re mind isn’t clouded by processing visual information the more of your mind can be focused on self improvement and gaining knowledge and wisdom. 

Blind martial arts

Back where you learned to be a monk you trained to fight with a blindfold. Up until now you haven’t been confident enough to put one on during actual combat but now at 3rd level your ready to put on the blindfold and trust only your ears. As long as you can hear but can’t see you gain the following benefits.

• you have blind sense 
• you have proficiency in dex and wis saving throws 
• you can spend a ki to make the attack action if an attack misses you 

all abilities from this subclass can only work if the requirements for this ability are met 

Ki sonar

At 6th level you can send out a pulse of ki to scan your surroundings. By spending two ki points you gain the following benefits for 1 minute 

• you no longer need to be able to hear In order to use any of this subclasses abilities 
• You can ask the dm to describe the surrounding area in a mile long radius circle as many times you want for the duration 
• you have advantage on perception checks
• you have advantage on dex checks  

Blinding strike

At 11th level you can disrupt the flow of ki from an enemies eyes. By spending a ki point when you attack you can make the target make a constitution saving throw and if they fail they are blind until the end of your next turn.

Unseeable fury

At 17th level you are adept at taking advantage of the fact your enemies aren't trained in blind combat. If a hostile creature has the blind condition you can spend one ki to get an extra turn at the end of their turn. During this turn you can only interact with the blind creature and you have an extra attack you can do on that turn. If you spend 3 ki points you can do it if the target is simply in darkness.