The psion draws real power from his mind. His power is a logical expression of lore attained through ongoing self-study. His aggressive powers do not freely scale as do the spells of arcane and divine casters, but he enjoys supreme flexibility in accessing those powers. A psion must choose one discipline in which to focus, at the cost of losing access to the signature powers found in other disciplines -so in a sense the psion character class is six classes rather than one. A shaper (a psion who has selected meta creativity as her discipline) is a very different character from a telepath (a psion whose discipline is telepathy).
Hit Dice: d4
High Saves: Will
Weapon Proficiency: Simple Weapons,
Armor Proficiency: Light Armor. Any shields, medium- or heavy armors interfere with power manifestation with arcane spell failure chances.
Skill Points: 2 + Int Modifier (4 + Int Modifier at Lvl 1)
Class Skills: Bluff, Concentration, Craft (Alchemy), Craft (Armor), Craft (Weapon), Diplomacy, Heal, Intimidate, Listen, Lore, Spellcraft, Spot, Survival, Use Magic Device
Power Manifestation: A psion does not cast arcane spells or draw upon the powers of gods or eldritch beings, but rather manifests psionic powers drawn from their own mental prowess. Manifesting such powers is not impeded by the use of light armor, but any armor of a class heavier than light, and shields of any sort will incur power failure in a similar manner to arcane spell failure. A psion gains two powers at first level, dictated by the discipline chosen, and may choose two new powers to manifest at each level thereafter. New power levels are accessed at every odd level until level 17, whereapon 2 level 9 powers are acquired at level 18 and 20 respectively (no powers are granted at 17 or 19). Note: Once chosen, a psion's power cannot be un-learned or exchanged for another save through de-leveling with the Styx Oarsman. A psion's casting progression is controlled by a feat which updates every even level until level 20. If attempting to level a psion and the power selection menu is blank, try resting to update the casting progression feat.
(NOTE: If taking psionic PrCs, you will likely run into the situation where you have taken the maximum 4 level 9 powers but still have power-granting levels remaining. A blank menu will appear and though you have 2 'bonus feats' you will have nothing to select. At this stage (after grabbing 4 level 9 powers) this is NORMAL (not a bug needing reporting) and the blank menu can be skipped.)
Power Point Pool: When a psion manifests a power, he does so by spending 'power points'. Metapsionics modify the power's cost, and a psion cannot manifest a power that costs more power points than he or she has levels in a manifesting class. A psion's power point pool increases with each level taken in the class, and can be modified or enhanced by several feats. A psion's Intelligence score grants them additional power points equal to their INT modifier * your manifester level * 1/2.
Psionic Disciplines: At first level, a psion must choose the discipline of psionics they wish to specialize in. While less restrictive than arcane specialization, with no 'forbidden' disciplines, there are nonetheless powers that a 'Telepath' (for example) can master that a psion of a different specialization will never be able to learn. The disciplines and their specialties are as follows:
Clairsentience (Seer) - Seeing the future and gathering information.
Metacreativity (Shaper) - Creating constructs and crystals out of raw Astral matter.
Psychokinesis (Kineticist) - Harnessing the raw energy of the mind.
Psychoportation (Nomad) - Manipulating space and time.
Psychometabolism (Egoist) - Transforming, healing, and enhancing the body.
Telepathy (Telepath) - Influencing, controlling, and attacking the mind.
Psionic Lash: A crude, but effective telepathic attack that all psions regardless of discipline learn. At will a psion may hurl a bundle of psychic energy directly into the mind of their foe. To creatures not immune to mind-effecting abilities, this deals 1d4 damage + 1d4 per every 3 levels of the Psion class. To non-psions, a failed will save causes 1d2 rounds of confusion in addition to the damage. To psions, a failed will save results in power point loss equal to double the amount of physical damage sustained by the lash.
Augment Power: Starting at level 1, a psion gains the ability to generally augment his powers in a manner similar to a wizard's metamagic. This basic metapsionic ability has a variety of effects depending on the power augmented. A power that is augmented costs 50% more power points than the base power cost, with a minimum of 1 extra power point cost.
Note: For a list of available powers take a look here.