Highly skilled in martial and psionic arts, zerths were capable of transporting between planes only using their minds. They were capable of innately casting plane shift once per day. In combat, they could also use their minds to inflict damage upon their opponents, through innately casting phantasmal killer.

Especially gifted zerths, known as "enlightened", were capable of even more extraordinary psionic feats, such as innately casting haste and teleport and enhancing their own defenses through psionic power.

Psionic Arts

Starting when you choose this tradition at 3rd level, you can use your ki to duplicate the effects of certain spells. As an action, you can spend 2 ki points to cast catapult, levitate, thought shield, and mental barrier without providing material components. Additionally, you gain the message cantrip if you don’t already know it.

Open Mind

At 6th level, you gain the ability to teleport using your psionic power. As a bonus action you can teleport up to 30 feet to an unoccupied space you can see. You can use this feature a number of times equal to your Wisdom modifier +1 (minimum of once). You regain all expended uses of it when you finish a short rest.

Additionally your mental fortitude gives you the ability to pierce into your opponent's minds with a lance of psionic power. On your turn you can spend 3 ki points to cast mind thrust.

Arena of the Mind

At 11th level, you have learned to take the combat into your opponent’s psyche, turning their image of you into their worst nightmare. As an action, you may spend 5 Ki points to cast phantasmal killer as a 4th level spell.

You also have now learned how to weave your ki to increase your movements. You can spend 4 ki to cast haste targeting yourself. 

Enlightened

At 17th level, the mastery of your mind has allowed you to reach an enlightened state. After spending an hour in meditation, you can cast the spell plane shift once per day as long as you spend that hour focusing on the plane you wish to go to, and have the material component (tuning fork) in hand during that time. 

You also gain the ability to cast intellect fortress and telekinesis for the cost of 6 ki points each.