Found this tidbit:

The Gray Ghost thieves guild in Gracklstugh has a number of psionic members -- mostly lurks but also multiclass duergar and derro psychic warriors and psions. The guild is embroiled in a bitter war with the Keepers of the Flame, an order of psion/clerics [Laduguer] that serve Themberchaud (young adult red dragon), the Wyrmsmith of Gracklstugh. The war began when Zunkhasp Saltbaron (LE male duergar lurk 14), the nominal leader of the guild, organized the theft of a dragon egg from Themberchaud's treasure hoard. Themberchaud did not lay the egg -- he is a male dragon -- but it might be his offspring or part of the spoils of one of his conquests. The enraged keepers declared war on the guild, throwing the everyday affairs of the city into chaos.

It's an old 3E article from 2007 in the "Class Chronicles" series, discussing psionic subclasses of certain races.

Nice continuity even if the (SPOILER) Saltbaron in the adventure isn't really involved in any detailed capacity.

I'd ignore the level specifications - my impression is that the inflation in NPC levels is gone from 5E. (I know there are no "NPC levels" in 5E but we can still discuss power in terms of Challenge Rating.)

More on this tangent within tags:

[sblock]Judging from OotA I would guess there are no NPCs with a CR in the double-digits, with the prominent exception of Themberchaud. This works because of bounded accuracy: while he could probably slay a dozen Stone Guards, he would die if he attacked the city and its defenders.

What I mean is that even if I wanted to make this Zunkhasp Saltbaron (or Werz, his relative?) one of the most personally imposing Duergar in the city, I would definitely not make him 14th level (or the CR equivalent under the old rules: CR 13).

5E is much more realistic about NPC power: a Gladiator is a 15 HD creature, but only CR 5. A Mage is a 9th level spellcaster, but only CR 6.

So even if I wanted a "14th level NPC spellcaster" that would "only" mean CR 9. If the NPC was less focussed on dangerous spells, as low as CR 5.

I still wouldn't introduce a NPC as potent as that unless it truly was an important NPC. The leader of a thieves guild (even a psionic one) doesn't qualify. (Why would a level 14 character be content in running a thieves guild? If it secretly controlled the entire city I could understand it, but "waging a war" against one out of several city factions? To me, at 14th level you're severely overleveled for that role. In 5E, that is. 3E was infamously crawling with high-level nobodies)

Perhaps Morndin Gloomstorm, the Laduguer High Priest, could rival Deep King Horgar in (personal) power, and even then a "clerical Mage" sounds much more appropriate than "level 14".[/sblock]

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