I have a system I've been designing just for my own games. I went back to OD&D's Eldritch Wizardry and 2e's Complete Psionics, and focused on the core idea that any character could develop a psionic wild talent under the right circumstances. Here's a snapshot of how I'm handling it...
PSIONICS (QUICKLEAF'S VERSION)
Psionics are mysterious powers from the untapped regions of the mind. Whereas magic draws on an external source – the Weave, accessed by studying words of power, praying to deities, consorting with patrons, or through magical bloodlines – sages conjecture that psionics may be a form of mutation. Adventurers who come into contact with powerful aberrations (e.g. aboleths, beholders, mind flayers), who venture into certain regions of the Underdark or the Astral Plane, who undergo psychic surgery, or who suffer extreme trauma may awaken their latent psionic potential. Events during the campaign, such as exposure to specific substances/energies may also trigger a roll on the Psionic Powers table.
A few powers refer to your psionic attack or save DC. Calculate them as follows:
Psionic attack = your proficiency bonus + Intelligence, Wisdom, or Charisma modifier (choose one).
Psionic save DC = 8 + your proficiency bonus + your Intelligence/Wisdom/or Charisma modifier.
Wild Talent (feat)
You gain a randomly determined psionic power; roll on the Psionic Powers table. If you roll a ‘1’ indicating psionic madness, record that roll and apply it to to your character, but also roll again. You may take this feat multiple times.
PSIONIC POWERS
d20 | Discipline | Description |
1 | Psionic Madness (d10) | You’ve touched the deep recesses of your mind… and something touched back. |
2-6 | Clairsentience (d20) | Clairsentience enables you to learn secrets long forgotten, glimpse the immediate future and predict the far future, find hidden objects, and know the unknowable. |
7-9 | Psychokinesis (d20) | Psychokinesis manipulates energy to move objects, melt or transform matter, and blast targets with raw energy. |
10-12 | Psychometabolism (d20) | Psychometabolism changes the physical properties of a creature, thing, or condition, allowing you to accomplish extraordinary physical feats. |
13-15 | Psychoportation (d20) | Psychoportation moves you, an object, or another creature through space and time. |
16-19 | Telepathy (d20) | Telepathy allows you to spy on and contact the minds of others, influencing or controlling their behavior. |
20 | Roll twice, or pick one | – |
PSIONIC MADNESS
d10 | Madness | Description |
1 | Aberration Link | A lasting connection was formed between you and an aberration (e.g. aboleth or mind flayer), allowing you to telepathically communicate with one another regardless of distance. |
2 | Hallucinations | You experience distracting hallucinations which are hard to distinguish from reality. Though they may interfere with concentration, they are only fleeting. |
3 | Hypersensitivity | Too much stimulus (e.g. crowds, loud noises, bright lights) overwhelms you, and your saving throws against such effects suffer disadvantage. |
4 | Hypnotic Suggestion | You are induced with a subconscious hypnotic trigger by some unfathomably horrific entity that will trigger at a future time. |
5 | Permeable Aura | After spending significant time around another person, you take on one of their roleplaying traits for a few hours. Magic and Insight checks detect that trait as if it were your own. |
6 | Psionic Interference | You experience bizarre dreams and you fail any attempts to communicate telepathically or understand telepathic communication. Telepathic communication used within 30 feet of you, or on someone within 30 feet of you, fails. |
7 | Psychic Clone | Whenever you can see your reflection, it acts as a twisted clone of yourself, its values a dark mirror of your own. This twisted clone yearns to assume physical form. |
8 | Psychic Vulnerability | You suffer vulnerability to psychic damage and develop a phobia of anything psionic in nature, such as aberrations, githyanki, wild talents, etc. |
9 | Split Personality | Your mind splits into two separate personalities, though you only have limited control when you switch between them. You and your DM can work together to determine your alternate personality’s nature. |
10 | Unreliable Premonitions | You have premonitions that may or may not come true, but at the time you are convinced they are inevitable. |
CLAIRSENTIENCE
d20 | Power | Description |
1 | All-Around Vision | You can see in a 360-degree circle around yourself, though this requires concentration to maintain. Creatures sneaking up on you from behind suffer disadvantage. |
2 | Aura Sight | You can feel the mood of a creature by concentrating intently on it for 1 minute, perceiving an outline of colors. Gain proficiency in the Insight skill if you don’t already have it. |
3 | Clairvoyance | As a bonus action choose a space within 60 feet that you can see; you project your vision and hearing as if you were standing there until the start of your next turn (or 6 seconds). |
4 | Danger Sense | By concentrating on your turn, you cannot be surprised and you know the general direction hostile creatures are coming from a few seconds in advance. |
5 | Detect Psionics | You can detect if a creature or object within 60 feet has psionic power by concentrating intently on it for 1 round. You also gain a sense for how strong its psionic power is. |
6 | Detect Spellcasters | You can detect if a creature or object within 60 feet can cast spells by concentrating intently on it for 1 round. You also gain a sense for how powerful a spellcaster it is. |
7 | Hypercognition | You can spend Inspiration to gain a clue from the DM that reflects your ability to perceive patterns and make deductions. If your Intelligence isn’t already 13, increase it to 13. |
8 | Incarnation Awareness | By concentrating intently on a dead creature within 5 feet for 1 minute, you determine how many times it has died and the general nature of its past life/lives. |
9 | Infravision | By concentrating on your turn, you can perceive heat signatures within 60 feet, allowing you to see any warm-blooded creatures or heat sources, even through walls. However, stone and metal (and anything else that conducts heat) blocks your infravision. |
10 | Know Direction | You always know true north and are immune to maze magic and effects. |
11 | Object Reading | When touching an object and meditating with it during a short rest, you gain a glimpse of its creation, its destruction (if destroyed), and the last creature interact with it. |
12 | Perceive Light | By concentrating on your turn, you can perceive light through tactile or auditory sensation, circumventing the blinded condition (provided there is ambient light). |
13 | Perceive Sound | By concentrating on your turn, you can perceive sound thru tactile or visual sensation, circumventing the deafened condition (provided there is ambient sound). |
14 | Precognition | You can spend Inspiration to learn about a future event or threat from the DM, though the DM determines the extent of the information you receive. If your Wisdom isn’t already 13, increase it to 13. |
15 | Radial Navigation | By concentrating on your turn, you know the direction and distance to the last fixed point that you meditated at during a short or long rest. |
16 | Remote Viewing | Once per long rest you can produce a psionic effect similar to the scrying spell. |
17 | Retrospection | During a long rest you can meditate with another creature and help it (or yourself) to regain lost memories or review old memories. The DM may call for a check. |
18 | Sense Aberrations | By concentrating on your turn, you become aware of the presence of any aberrations within 60 feet of you. |
19 | Sense Spirits | By concentrating on your turn, you become aware of the presence of any restless spirits (e.g. ghosts, haunts, specters, wraiths) within 60 feet of you. |
20 | Sensitivity to Psychic Impressions | By meditating in an area during a short rest, you gain a vague sense of the emotional history of the place you’re currently in (e.g. tragedy, war, madness, elation, reunion, birth). |