Psionic Discipline: Psychometabolism

Psychometabolism changes the physical properties of some creature, thing, or condition.

Psionic Casting

At 2nd level, you gain the Psionic Casting feature. When manifesting a power (i.e. casting a spell), you ignore any verbal and somatic components, and any material components that are not both consumed by the spell and have a listed gold cost.
This allows you to ignore spellcasting limitations based on components, such as not having a hand free, having your hands bound or being gagged. However, this feature does not allow you to cast spells when you are explicitly prohibited from doing so, such as when wearing armor you are not proficient with or when you are Polymorphed.

However, unless you use any abilities to hide it (such as the Subtle Spell metamagic feature), manifesting a power (i.e. casting a spell) is still readily obvious to onlookers, as it is accompanied by a telltale auditory, material, mental, olfactory or visual display emanating from you. Auditory displays can be, for example, a strange hum or ringing; material displays could consist of a short appearance of ectoplasmic residue; mental displays, a flash of static or aura that onlookers notice around you; olfactory, the sudden appearance of a familiar scent, or a smell of burning; and visual displays often involve scintillating colours or your eyes lighting up with psionic energy.
Whatever the form, these displays are never significant enough to create immediate consequences for the psionic creatures, allies, or opponents during combat, but they do indicate the use of magic and its user. 

Typically, the nature of a display depends on the kind of spell components are being ignored: Verbal components result in an auditory or mental display, somatic components result in a visual display, and material components result in a material or olfactory display.

Any feature or effect that would allow you to ignore spell components other than this ability, also allows you to conceal the corresponding displays.

Biofeedback

At 2nd level, you gain the ability to heal yourself. As an action, you can regain hit points equal to three times your wizard level. You must finish a long rest before you can use this feature again.

Shapechanger

At 6th level, you add the polymorph spell to your spellbook, if it is not there already. You can cast polymorph without expending a spell slot. When you do so, you can target only yourself and transform into a beast whose challenge rating is 1 or lower.

Once you cast polymorph in this way, you can’t do so again until you finish a short or long rest, though you can still cast it normally using an available spell slot of the appropriate level.

Bolstered immunity

Starting at 10th level, you can become immune to disease, the poisoned condition and to poison damage. 

Improved Biofeedback

Starting at 14th level, you can use your reaction to enter a biofeedback trance. When you use this ability, you gain resistance to all damage except psychic for 1 minute.

You can use this ability once per long rest for free. After that, you must expend a 4th level or higher spell slot to use it again.