Your training allows you to harness the mystic energy of ki. Your access to this energy is represented by a number of ki points which reset daily. A Monk starts with the maximum amount of Ki Points, which is 3 and a limited number of Ki Abilities. After reaching Mastery, a Monk is able to fully realize the power of their Ki and unlocks the remaining Ki Abilities for their use.

Currently implemented Ki abilities are:

Deflect Missiles
Once per combat when struck by a ranged, physical projectile, or spell, you may immediately retaliate with a dart for 1d8 + casting modifier at the cost of 1 Ki.

Ki Empowered Strikes
At the cost of 1 Ki, you may make a third attack with an Improved Unarmed Strike after your initial Attack action, and Secondary attack. (1 handed, 2 handed, Improved Unarmed Strike)

Stillness of Mind
At the cost of 1 Ki, once per day you can still your mind by using your action to end one effect on yourself that is causing you to be charmed or frightened.