- Arcane Warlocks are a bit of a problem because their version of spellcasting does not sit well with how I envisage defiling & preserving working (and of course a lot of the things they might pact with do not exist). We could have primal elemental-pact warlocks which are thematically another kind of Cleric.
- Psionics are distinct from magic, both thematically and mechanically. They are not just another form of magic, and certainly do not use spell slots. This is the most important for me, and the one I least expect to see in an actual 5e Dark Sun.
I have been wondering lately if Warlocks aren't a better fit for replicating what 2nd edition psionics was like than the sorcerer or wizard.
Reason #1. They didn't have a huge array of powers. A 1st level psionicist had access to 1 science and 3 devotions, all within the same discipline. By 7th level, he would have 4 sciences and 12 devotions. By 20th they would max out at 10 sciences and 25 devotions.
Sciences were on the level of a 3rd- 5th level spell, whereas devotions were 1st level or lower. Maybe even 2nd.
Some example sciences: Clairaudience. Clairvoyance. Detonate. Telekinesis. Complete Healing (only for yourself!) Metamorphosis. Teleport. Teleport Other.
Some example devotions: Hear Light. Know Location. Animate Object. Control Flames. Catfall. Chameleon Power. Dimensional Door. Astral Projection.
Some powers had prerequisites, like Dominate, a Science, required Mindlink, another science, as well as Contact, a devotion.
There was also a Metapsionics discipline, which was more or less a catch-all for all of the powers that had a level requirement.
So, much like the warlock, a psionicist had a few specific, but powerful abilities they could use often. Those were coupled with a collection of abilities that were cantrip-like, though a few were pretty hefty.
Reason #2: While much ado has been made of psionic strength points over the decades, it is worth noting that the 2e version had psionicists regaining PSP's
hourly... Provided they weren't doing anything strenuous. This, to me, bears more resemblance to the Warlock's short rest than the Sorcerer's daily spell points.
Reason #3: I might be stretching here, but psionics was double-edged, much like the warlock's pact.
Psionics had a built-in critical failure system, but most failures fit into the following categories:
1- your target knows what you were trying to do. (Psionic invisibility makes everyone around you aware of your attempt and desire to be invisible. ha.)
2- temporary loss of a few points of ability score.
3- nothing.
A few had some hair-brained flaws. Some were a complete reversal of whatever it was you were trying to do, which could be a real problem. Probably the most deadly were the ones that made your psionicist appear to be dead unless they were violently struck, which is a good way to end up actually dead if you didn't tell the party what you were up to or what might happen.
While critical fumbles probably don't need to be carried forward, the idea that psionics might actually be dangerous to the practitioner might serve to fill the hole that the patron once filled. For example, a psionicist suddenly finding themselves undergoing an impromptu spirit journey is in keeping with 2nd edition psionics. (Much like some 5e DM's might use a warlock patron as a plot device.)
Eh. I said it was a stretch.
