Way of the Mind Knife

Centuries past, an order of human monks went on pilgrimage throughout the planes seeking those who could teach them the path of true discipline and power. Every place they visited pointed them in the same direction: to Limbo and the Githzerai. Only a handful of the order that set out on that pilgrimage returned, and those that did were different. The monks had not simply learned the techniques of the Githzerai: they had adapted them to their human minds and for use on the material plane. Most notably, they focused their psychic force into a blades that they projected from their hands.

Psionic Knife

Starting at third level, you can use your psionic energy to manifest blades that disrupt your foes’ minds.

Your unarmed strikes deal your choice of psychic, piercing, or bludgeoning damage each time you hit.

In addition, you can use a bonus action to increase the reach of your unarmed strikes by 30 feet until the end of your turn. Such attacks must deal psychic damage.

Psychic Slash

When you channel ki into your attacks you augment your psionic knives. Once per turn when you hit a creature with an attack granted by your Flurry of Blows and that attack inflicts psychic damage, you can impose one of the following effects on the target:

Life Drain. You gain temporary hit points equal to half the damage your attack deals.

Invoke Terror. The target must succeed on a Wisdom saving throw or become frightened of you until the end of your next turn.

Invoke Wrath. The target suffers disadvantage on all attack rolls against targets other than you until the end of your next turn.

Astral Slide. You teleport the target up to 10 feet to a destination you can see.

Instill Weakness. The target suffers disadvantage on all Wisdom, Intelligence, or Charisma saving throws (your choice), until your next turn.

Mastery of Thought

At sixth level, as an action, you can spend 2 ki points to cast detect thoughts, calm emotions, mind spike, or suggestion, without providing material components.

Purity of Mind

Starting at level 11, your mind cannot be read unless you allow it. You have advantage on saving throws to resist any sort of mind control, including effects that impose the frightened or charmed conditions. Additionally, your saving throws against effects that lower your Wisdom or Intelligence automatically succeed.

Synaptic Flood

By striking deep with your mind knife, you can flood an enemy's consciousness with overwhelming information. When you hit with an unarmed attack, you may spend 3 ki to force your target to make an Intelligence saving throw. If they fail, they take (10 – their Intelligence modifier) d10 psychic damage and are Stunned for 1 minute. At the end of each of their turns they can repeat the save to end the Stunned condition.

If they succeed the initial save, they are Stunned until the end of your next turn and take half damage.

You regain the use this ability after a short or long rest.

Targets with mental fortitude provided by Purity of Mind or equivalent features automatically succeed on their saves.