Way of the Cobalt Soul
The monks of the Cobalt Soul are the embodiment of the maxim: "Know your enemy." Through tireless research, they steel themselves against the unrelenting tides of evil. Through rigorous training, they learn to break through their foes' mental and physical defenses. Then, once the fight is done, they record their findings for future generations of monks to study.
Starting at 6th level, you can precisely strike a hidden cluster of nerves on a creature, temporarily preventing it from masking its true thoughts and intent. When you hit a creature with an unarmed strike, you can spend 1 ki point to force it to make a Charisma saving throw. On a failed save, the creature is unable to speak a deliberate lie, and all Charisma checks directed at the creature are made with advantage for up to 10 minutes. You know if it succeeded or failed on its saving throw. And affected creature is aware of the effect and can thus avoid answering questions to which it would normally respond with a lie. Such a creature can be evasive in its answers as long as the effect lasts. If you wish to impose this effect on a creature without injuring it, you can attack the creature to simply touch it, dealing no damage on a hit.
Also at 6th level, you have extensively studied the history and lore. You learn one language of your choice, 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 skill. 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.
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, you may spend 1 ki point to take an additional reaction. You can use only one reaction per triggering effect.
Upon reaching 17th level, you've gained the knowledge to manipulate a creature's ki to undermine their fortitude. When you hit a creature with an unarmed strike, you can spend 3 ki points to cause the creature to gain vulnerability to one damage type of your choice for 1 minute, or until the end of a turn in which it has taken damage of that type. If a creature has resistance to the damage type you choose, this resistance is suppressed for 1 minute, rather than gaining vulnerability. A creature that is immune to the damage type you choose is unaffected. A creature who is affected by this feature cannot be affected by it again for 24 hours.
Extort Truth
Starting at 6th level, you can precisely strike a hidden cluster of nerves on a creature, temporarily preventing it from masking its true thoughts and intent. When you hit a creature with an unarmed strike, you can spend 1 ki point to force it to make a Charisma saving throw. On a failed save, the creature is unable to speak a deliberate lie, and all Charisma checks directed at the creature are made with advantage for up to 10 minutes. You know if it succeeded or failed on its saving throw. And affected creature is aware of the effect and can thus avoid answering questions to which it would normally respond with a lie. Such a creature can be evasive in its answers as long as the effect lasts. If you wish to impose this effect on a creature without injuring it, you can attack the creature to simply touch it, dealing no damage on a hit.
Mystical Erudition
Also at 6th level, you have extensively studied the history and lore. You learn one language of your choice, 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 skill. 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.
Mind of Mercury
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, you may spend 1 ki point to take an additional reaction. You can use only one reaction per triggering effect.
Debilitating Barrage
Upon reaching 17th level, you've gained the knowledge to manipulate a creature's ki to undermine their fortitude. When you hit a creature with an unarmed strike, you can spend 3 ki points to cause the creature to gain vulnerability to one damage type of your choice for 1 minute, or until the end of a turn in which it has taken damage of that type. If a creature has resistance to the damage type you choose, this resistance is suppressed for 1 minute, rather than gaining vulnerability. A creature that is immune to the damage type you choose is unaffected. A creature who is affected by this feature cannot be affected by it again for 24 hours.