Here we cover the lower strata of Gauntlgrym, where the place’s greatest dangers live.

Duergar Mines

The duergar of Gauntlgrym live in this sector, which lies deeper than most of Gauntlgrym. The book says they’ve been here for “a few generations”, which is a lot longer than I thought before even if these are human generations. Their situation, however, still matches: they’ve taken over old mining tunnels and dug new ones under the direction of their leader Kholzourl.

They’ve unearthed several veins of useful metal, including iron, silver, mithral and hellthorn (the one that likes infernal enchantments). Their work is ceaseless, grueling, and mostly done by slaves, which they replenish by capturing any non-duergar they lay eyes on down here. Tunnels built by the original dwarves show their characteristic sloped walls and tend to be both safe and clean. Duergar tunnels are slapdash and hazardous, sometimes nearly vertical due to their leader’s need to go ever deeper. Some of these shafts are so deep that they contain semi-permanent work camps where duergar and enslaved workers live instead of going back to the city at the end of every day.

The duergar don’t care about the big mithral gates. They got here from below, via tunnels that link their camps to the deep Underdark. Some of these tunnels have since been taken over by plaguechanged mind flayers, which are as much a cause of injury and death as the work itself.

Somewhere in the mines is also a temple to Asmodeus built from desecrated material taken from the Iron Tabernacle, which Kholzourl uses to commune with his god and summon the occasional devil.

And why exactly are the duergar so intent on digging ever deeper? Only Kholzourl and the GM really now. The book gives us several possible reasons - GMs can either pick one or use them as inspiration for a bespoke sinister plot.

  • Hellthorn comes from a meteorite that fell here in primeval times, and the main body of the thing contains far more power than the mere shards that have been found so far. Maybe it contains an alien diabolic entity, millions of years old, waiting for the moment when it is found and awakened.

  • The duergar want to drain the magma from Maegera’s resting place and transport her slumbering form to some place where she can wake up and destroy an enemy of Asmodeus.

  • The mining is just a cover and their actual goal is to observe the mind flayers and track down their aboleth masters. The duergar suspect they want to open a permanent portal to the Far Realm and want to hijack the procedure so the portal leads to Hell instead.

  • Or maybe the interaction of all the different types of bad magic that bathe this region (infernal, aberrant, necromantic, oh my!) has created something terrible underground that they wish to claim for themselves.

The Fiery Pit

The lowest halls of Gauntlgrym are occupied by this enormous lake of magma, at the center of which spins a white-hot whirlpool that marks Maegera’s resting place.

The prison devised by the ancient mages if Illusk used bound water elementals fed by a continuous stream of sea water pumped here by magical means. The system could only be turned off by a true heir of Delzoun. The cataclysm happened when Valindra found one to pull the lever, causing Maegera to nearly awaken. Drizzt and his buddies prevented a full awakening back then, but the partial one was still enough to ruin Neverwinter.

Unfortunately one of the channels had been destroyed, and so was not reactivated when the rest of them were. This caused the binding to become imperfect and to slowly fade over time. Now Maegera is dangerously close to another awakening.

Maegera is meant to be used as a looming threat - the bad guys want to wake her, the PCs want to stop that from happening. PCs could fix the broken arcane pump by using the notes found in the Waterclock Crypt in Neverwinter, which would make the whole thing stable once more.

Unless of course the Heir of Delzoun PC is foolish enough to pull the “off” switch again, causing another cataclysm. Then the whole Sword Coast is due for a TPK.

The Great Forge

In addition to the water elemental-based restraints, the structure around Maegera also contains a complex network of pipes and wires made from all sorts of enchanted and rune-carved metal, from copper to adamantine. These act as conduits for the primordial’s power, which was siphoned to this sector of the city.

The heat arrived at a great adamantine pyramid known as the Burning Heart, which collected it and distributed it to the various forges and manufactories in the sector. This heat could melt through any metal in short order, making it extremely easy to shape and ensuring the resulting products would carry a little of Maegera’s power with them.

PCs investigating the Forge can find remains of an ancient battle here, and will find with the appropriate skill tests that the bones of the invading force belong to legion devils.

The Heart itself can also be investigated by characters competent in Arcana. Beating a DC of 11 reveals the obvious (lots of fire magic!); beating a 16 reveals this fire magic is being moderated by water magic; and beating a 23 reveals that the energy is being drained by a third party (the aboleths, which use it in their research).

“Normal” areas of the Forge are subject to the Unearthly Heat terrain effect, and since Maegera is partially unbound some terrain here can display more overtly supernatural fire features.

Breaching one of the conduits from the Heart or the Forge will bathe the offending character in primordial fire magic, making them resistant to fire and better at using fire attacks, but vulnerable to and worse at using some other element of the GM’s choice. Also, they get a bonus to Diplomacy with elemental creatures and a corresponding penalty when dealing with immortal ones.

The character loses three healing surges when this happens, and it wasn’t clear to me whether they could be recovered normally. The mutations are permanent until cured by Remove Affliction or an equivalent power. A cure removes all effects - there’s no way to keep just the beneficial ones!

The Deepest Depths

This is the part of Gauntlgrym that connects to the Underdark. The duergar originally came in through here, but the place has since become very inhospitable even to them. Many species of aberrant creature dwell in these dark passages, chief among them the plaguechanged mind flayers that are giving the duergar trouble. Their mission is to prevent anyone from messing with Maegera, and thus from getting in the way of the AbSov’s remote experiment with her.

This means they fight the duergar, but they aren’t any less evil than their foes. Like most Underdark villains mind flayers are fond of slavery, and they keep their captives here as well.

This region is also where the dwarves built secure vaults to store a variety of horrors they found in their delves. Most are still secure, but some have been opened over the centuries. One of the vaults that are already open is the one that housed the original population of dire corbies, and which has become their largest nest. They keep a lot of treasure there that no other faction has managed to claim yet.

Beneath even this, you get into tunnels that aren’t part of Gauntlgrym, and which snake their way downwards to the Underdark. Whatever is down there is out of scope of the campaign. It could perhaps be an interesting segue into Paragon Tier when the PCs do finish it, should the group be willing.

Impressions

The areas detailed in this post have a definite “endgame” feeling. Whatever your reasons for coming to Gauntlgrym, if you’re here you’ll need to deal with the mess of adversarial factions described in this post, finish what Drizzt and company could not, and make sure Maegera stays asleep.

This would be a fitting end to a campaign centered on the Heirs of Delzoun, but others might go from here to the bottom of the Chasm as they follow the clues left by the mind flayers to their real masters.

Conversely, if the group doesn’t include any heirs or anyone else who’d be interested in the lost city, Gauntlgrym can be safely and entirely removed from the campaign. Just say that Maegera is in no danger of waking up, and focus on those elements that are relevant to your players.