Way of the Arach-knight

You learn the mystic arts and ways of a spider, and gains some of its benefits.

Marked for Death

Starting at 3rd level, when you hit a creature with an attack granted by your Flurry of Blows, you can mark it. When you mark a creature all attacks you make against it have advantage. This benefit lasts until the end of combat, and you can do this once per short/long rest. You may only have one creature marked at a time.

When an marked creature misses you with an attack, you can use your reaction to make an unarmed strike against it if it’s within your reach.

Web of Lies

Starting at 6th level, you can precisely strike a hidden cluster of nerves on a creature, temporarily weakening it to your deceptions.

When you hit a creature with an unarmed strike, you can spend 1 ki point and force it to make a WIS saving throw. On a failed save, the creature will gain double disadvantage (Roll 3 dice, take the lowest) on saves that require discerning a lie from you. This effect can be imposed on the creature without dealing damage to it.

You know whether the creature succeeded or failed its saving throw, and all saves that are made to discern a lie from you. 

Spiders Erudition

Also by 6th level, you have extensively studied the history and lore within the archives of the Arach-Knight. You gain a climbing speed of 25ft., and you gain proficiency with one of the following skills of your choice: Arcana, History, Investigation, Nature, or Religion. If you already have proficiency in one of the listed skills, you can instead choose to double your proficiency bonus for any ability check you make that uses the chosen proficiency.

You gain an additional language and an additional skill proficiency from the above list (or you can double the bonus of an existing proficiency from the list) at 11th and 17th level.

Speedy Reflexes

Starting at 11th level, you’ve honed your awareness and reflexes through mental aptitude and pattern recognition. Once per turn, if you’ve already taken your reaction as an opportunity attack, you may spend 1 ki point to take the same attack again, with the second attack having advantage.

Spiders Erudition (Additional)

You gain a bonus to your climbing speed and an additional skill proficiency from the above list (or you can double the bonus of an existing proficiency from the list) at 11th level.

Critical Strikes

Upon reaching 17th level, you’ve gained the knowledge to strike with unrelenting speed. When you perform a critical hit on a creature with an unarmed strike, you can spend 3 ki points to attack a further 3 times. You can use this multiple times, and if one of the 3 further hits were also a critical hit, you may spend another 3 ki points to attack 3 more times, ect.

Spiders Erudition (Additional)

You gain a buff to your climbing speed and an additional skill proficiency from the above list (or you can double the bonus of an existing proficiency from the list) at 17th level.