The Monsters Know What They’re Doing

Moar duergar! The duergar mind master is the last of the CR 2 duergar, the one with the ability contour of a spellcaster but no actual spells. What it does have is Mind Mastery, a feature with a 60-foot range which requires an Intelligence saving throw to resist. More to the point, it targets one creature within 60 feet and requires a DC 12 Intelligence save to resist.

This feature, frankly, is terrible. Even a level 1 PC who’s dumped Intelligence still has a 40 percent chance of succeeding on this saving throw. It’s a straight-up waste of an action in any circumstance save one: as part of an ambush. In this instance, a hidden mind master can use Mind Mastery against a target without giving away its position or even its presence if it fails, since Mind Mastery is technically neither an attack nor a spell. If it succeeds, it gets to force an opponent to sucker-punch one of their own allies—or, depending on the local terrain, walk directly into a chasm or a river of lava or something. With Intelligence 15, a mind master is smart enough to know not to bother using this feature in open combat.

So forget treating it as a spellcaster; we’ll pretend that its Intelligence is nothing special after all and it’s just another shock trooper, using Dexterity for offense as well as defense. (more…)

The central question in running duergar—which otherwise are simple and straightforward brute fighters—is when to use Enlarge and when to use Invisibility, the complication being that Enlarge both breaks invisibility and takes an action to execute, preventing a duergar from attacking on the same turn. Thus, any additional damage it deals from being Enlarged has to make up for the round in which it deals no damage at all. As I note in an earlier post, the break-even point for ordinary duergar is in the third round of combat. Over just one or two rounds, Enlarging doesn’t add enough damage to make up for the lost round. Over four or more, it offers a clear advantage. Thus, the more likely a fight is to drag out—in other words, the more evenly matched the two sides—the greater the benefit of Enlarge. Invisibility, meanwhile, is really useful only for either ambush or flight, since it’s a once-per-combat feature that’s disrupted by attacking, casting a spell or Enlarging.

Interestingly, not all the duergar in Mordenkainen’s Tome of Foes possess Enlarge and Invisibility. In fact, only four of the seven duergar variants in Mordenkainen’s have these two features, and one of them has Invisibility on a 4–6 recharge, resulting in a big increase in the breadth of its usefulness. Also, while most of the variant duergar are also brutes, one is a quasi-spellcaster (it has no spells to cast, but it does have an Intelligence-based long-distance offensive ability), and one is a shock trooper. Finally, alongside those seven variants, there are two profiles of constructs that duergar employ. As I go through the various stat blocks, I’m going to focus primarily on how these variants differ from run-of-the-mill duergar. (more…)