Personally, I'd use something like this. A fairly minimalist and hacked up version based on the Sorcerer.
I agree about the minimalism! Elegant: as simple as possible but not simpler − and as versatile as possible, useful for various character concepts.
I am less of a fan of fiddly underpowered Sorcerer mechanics. But Warlock is popular, and its high level slots from the arcanums satisfy my desire for a fullcaster.
Honestly, while there's a good argument to be made about having psionic abilities divorced entirely from magic,
I am hardcore in the camp of "magic-psionics transparency".
That said. 5e has power sources, and the psionic power source can have meaningful mechanical weight such as innate spellcasting.
the 5e designers have committed pretty hard to the idea that pretty much all supernatural powers should be mechanically represented by spells, simply to increase interchangeability and avoid having to support another subsystem in future sourcebooks.
The Warlock is a standard 5e spellcaster. But its invocations can open the door to unusual mechanics.
Level 1: choose any 1 of Int, Wis, Cha to be your spellcasting ability.
Yes!
The concept of a Psion can be intuition (Intelligence Investigation), willpower (Wisdom), or self-expression (Charisma). The player chooses the casting ability during character creation.
One of your saving throw proficiencies is your spellcasting ability, the other is Con.
For now, I am going with Wisdom and choice of Intelligence or Charisma. But the player can use Wisdom for Concentration checks instead of Constitution.
Psionics require no components. Perhaps a 1/long rest ability to meditate to regain expended sorcery points and/or spell slots, cos the sorcerer is arguably a bit underpowered on that front right now. Power reserve is handled by the standard sorcerer ability of being able to swap sorcery points for spell slots.
The "psionic power source" means innate spellcasting without components.
A really quick and dirty mechanism for separating psionics from magic. Non-psionic characters trying to dispel psionic effects roll at disadvantage, and vice versa, non-psionic characters using Detect Magic to detect psionics need to pass a Perception check against the spell save DC, and vice versa.
I feel strongly about "transparency" because of gaming balance and normal spellcasting.
But there is room to play. For example, perhaps one of the "talents" (invocations) can modify a spell that has the psionic tag.
A spell list separate from the regular sorcerer spell list. Lose the flashy evocations, conjurations, transmutations, instead gain various divination, enchantment, buffing spells from the bard, druid, cleric lists.
Well, "fire starter" and other elementalists are "flashy". But I feel we can restrict these to a specific subclass.
POSSIBLY some sort of 'tell', in place of components? Perhaps when you manifest a psionic spell, there's a perceptible effect in a 15 foot radius of you, maybe the temperature drops or people hear whispering in their heads, or a sense of mental pressure, or maybe your eyes glow. This is more flavour than anything else though.
We can think this thru. 5e already has psionic rules, and it includes innate spellcasting without components. But perhaps we can add a benefit if using a Verbal (speaking or chanting to focus ones mind), visible aura, or other casting "display".
Subclasses grant additional spells known at level 1, a bit like domain spells.
Cool.
At 6th level, psions can cast their special subclass spells that are not the highest level they can cast, with a slot one lower than normally required. At 14th level, they can maintain concentration on two spells simultaneously as long as both spells are from their subclass list.
We will figure out the spell lists. The 5e spells that are already appropriate for the Psion. Plus, identify which spells are missing that we need to write up.
Subclasses:
- mindbender: gets all the good telepathic/psychic damage spells, and phantasmals. Additional features: free telepathy, psychic damage resistance.
- shipfloater (for want of a better name - this is what dark sun called telekinetics, and I like it as a not-too-science-y psionic term even though its very setting-specific): telekinetic and projectile spells like Catapault, plus stuff like Slow/Fly etc which plausibly have a telekinetic origin. Bonus feature is free Mage Hand, a reaction to grant resistance against incoming missile weapons, and any telekinetic effects have no visible effect if desired.
- firestarter: bunch of fire spells. Bonus fire resistance and Elemental Adept
- seer: every divination spell, from every class, plus some abjuration etc spells that can be interpreted as effects of precognition or something. Bonus feature, luck rerolls like a divination wizard
- shaper: a bunch of transmutation and abjuration spells with a 'self only' restriction added - enlarge, polymorph, stoneskin, cure wounds, barkskin etc. Bonus feature would be granting self darkvision or natural weapons or water breathing etc, and possibly extra HP and some sort of option for making melee attacks using spellcasting ability, cos this is a combat-focused subclass and the sorcerer is a bit fragile for that sort of thing otherwise. Besides, if I'm gimping their transmutations to be self-only, it's only fair they get more powerful features in exchange.
Yeah the Psion class has many subclass concepts.
Maybe divide up the spell list into psionic disciplines. The let the player pick any two disciplines. One of these disciplines must correspond to their subclass archetype.
I haven't even TRIED to balance this, but that's the shape of how I'd do it.
Yeah. Me too. I care about balance. Alot. But we can balance it later. First lets get the concepts down.
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