Underdark
Tavern tales across Faerûn’s sunlit lands whisper of the Underdark, a lightless, subterranean realm that is home to fabled races and ancient, unspeakable evil. It is a domain of primeval mysteries and unending war, a hidden world of cruel masters and hopeless slaves, filled with monstrous races that were old before humans were born. It is a dank, dismal place of fungus, rot, and slime. It is a land where a few lucky merchants have found a lucrative trade, but where many more have been slain (or worse) for their effrontery. So dire is the reputation of the Underdark and its denizens that mothers caution their children to behave, lest the dark elves steal them away.
A proper account of the Underdark must include the cold
machinations of the hateful illithids, the unwholesome cities of
the drow elves who pay homage to the bitter Spider Queen, and the
unending servitude of the lesser creatures that fall into the
clutches of these two races. Unlike the upper world, where civilization
and the light of day protect travelers from horrors, the
Underdark holds the promise of deadly peril. Illithids, drow, phaerimms,
and aboleths vie for supremacy in its dark tunnels and sunless
seas. They fight one another with armies of slaves, terrible and
ancient magic, and mind-shattering psionics for control of the
encompassing tunnel systems and the extended caverns, vaults,
cavities, gaps, and nodes that riddle the earth beneath Faerûn. The
Underdark is literally an entire world, most of which is inhabited
by monstrous and evil creatures that shun the daylight. Hundreds
of independent cities, towns, and strongholds are scattered
throughout the caves and caverns that make up this realm.
Tunnels in the Underdark extend for miles, some ballooning
into caverns thousands of feet across, only to shrink to spaces too
narrow for a halfling to squeeze through. The largest cavern
halls are often representations of the surface in miniature, with
hills, valleys, underground rivers, and lakes. Most races native to
this realm make use of the walls and ceilings of their caverns,
accessing the higher levels via natural or magical flight or levitation,
or even wall-crawling mounts such as giant spiders and
certain breeds of lizards.
The Underdark is divided into three levels. The upper Underdark
(Upperdark) is close to the surface, and its residents have
considerable interaction with surface races. The inhabitants of
the middle Underdark (Middledark) tend to see surface races as
potential slaves. The lower Underdark (Lowerdark) is an incredibly
strange place filled with alien societies and bizarre cultures
hostile to those unlike them.
An Underdark Primer
While many surface dwellers regard the Underdark as all the
same (one big cave, infested with hungry monsters), the wise
adventurer prepares by studying what surface dwellers know
about the Realms Below before venturing underground. Knowing
what sorts of creatures and dangers lurk at what depths
might mean the difference between life and death.
The Underdark is divided into three general levels: The
Upperdark, the Middledark, and the Lowerdark. The Upperdark The Middledark The LowerdarkExploring the Underdark
What squelches through unlighted corridors
miles below the daylit surface
world? What secrets of ancient vintage
rest behind long-cooled barriers of solidified magma? What perils
and terrors await those foolhardy enough to venture into such a
dismal and dangerous environment? Adventurers from all over
Faerûn dare the depths of the Underdark in search of fame, fortune,
and power, but all too often they find only death—or fates
even worse than death.
Geology and Environments
A cave is a natural opening in rock that is large enough for creatures
to enter. The Underdark, simply put, consists of a linked
network of several titanic cave systems. Large portions of it do
fit the definition of “a natural opening in rock,” but the Underdark
also encompasses areas of deep water that hide coral caves,
hollowed-out sections of ice in which creatures live, and places
where fungus, bone, or even pure force form “caves.”
Underdark terrain is dynamic and changeable. A map drawn
a few decades ago may show tunnels that have long since collapsed,
or lakes that are now dry. Terrain can change gradually
over the course of decades, centuries, and millennia, or swiftly as
a result of an earthquake or volcanic eruption.
Topography Rocks and Rock FormationsThe Underdark Environment
Walking through wild caves without end is different than stalking
monsters in a dungeon near the surface. Travelers venturing
into the Underdark enter a world in which nothing can be taken
for granted. Vast portions of the Realms Below are wastelands
devoid of food, water, and even light.
Light in the Underdark Air in the Underdark Climate in the Underdark Ecology in the Underdark Underdark HazardsSpelunking
When traveling in cramped natural tunnels and through
narrow, low corridors that vary widely in diameter, it is difficult
to move as quickly or fight as efficiently as normal.
Cramped Spaces Climbing Access Getting LostUnderdark Encounter Tables
The Underdark is a vast region encompassing more square miles
than can easily be calculated, especially considering the three-dimensional
nature of it. Outside “settled” caverns and vaults,
the dark rootways below the mountains and plains of Faerûn
constitute a wilderness.
Geography
Faerûn’s Underdark includes drow cavern-cities, sunken
aboleth strongholds, entire realms of mind flayers, andwondrous vistas shrouded in everlasting darkness. This
chapter describes some of the most notorious, important, and
incredible locales in the Realms Below.
The locales described here do not represent an exhaustive
list of the Underdark realms. Uncounted hundreds—perhaps
even thousands—of deeply buried caverns and lightless cities
exist beneath Faerûn, and virtually every surface-world dungeon
seems to connect to murky depths from which all sorts of
horrors can spew forth. Consider the places discussed in this
chapter to be the ones that knowledgeable surface folk know
of, and a sampling of the types of places that deep-delving
heroes might explore.
Underdark Domains
Faerûn’s Underdark is not a single, continuous cavern system,
and even places on the same level may not connect to each
other. The existence of Underdark settlements beneath Waterdeep
and Raven’s Bluff, for example, does not mean that it is
possible to travel from one city to the other underground. In
fact, the Underdark consists of a number of discrete domains. A
domain is simply a collection of Underdark locales among which
underground travel is reasonably easy. In certain places it may
be possible to trailblaze a route from one domain to another, but
then again, it may not.
An Underdark domain is something like a large island in the
surface world. It may feature several distinct terrains and cultures,
but it’s possible to travel all over the island without having
to set sail on the ocean. Similarly, two locales in a single domain
are connected by enough cave systems, tunnels, and other passages
to enable travel from one to the other without leaving the
Underdark. Cities and settlements in the same domain are much
more likely to engage in diplomacy, trade, or warfare than cities
in separate domains. Like the continents or regions of the surface
world, domains tend to group disparate cultures together
and force them to interact with each other for good or ill.
Faerûn’s Underdark consists of seven major domains, a dozen
or so minor ones, and hundreds of otherwise isolated locales that
don’t appear to connect (at least not easily) to any other Underdark
networks. The major domains include the following.
The Buried Realms The Darklands The Deep Wastes The Earthroot The Glimmersea Great Bhaerynden The Northdark Old ShanatarSites of Interest
The following entries describe cities, ruins, dungeons, and other
points of interest that adventurers might wish to visit in the
Underdark. A history is given for each, and for some of the
more complex areas, descriptions of important sites and NPCs
are included.
Each of the following entries includes a parenthetical note about
its depth (Upperdark, Middledark, or Lowerdark) and its domain
(or geographical region, if it does not belong to a major domain).
Unlike surface cities, Underdark cities tend to be monocultural.
In many places, anyone who isn’t of the dominant race is
either a visitor or a slave. To reflect this arrangement, any city
with a sizeable contingent of slaves has a separate notation for
the slave population in its community statistics block. The population
and racial breakdown of the free residents is given first,
and then the slave population. Community assets are calculated
from the total population because slaves do help to generate
wealth, even if they don’t hold any of it.
Ammarindar Araumycos Blessed Seahaven Blingdenstone Boneyard Brikklext Cairnheim Chaulssin Ched Nasad Ch'chitl Cloakerhaven Deep Imaskar Deep Shanatar Deepburrow Doblunde Drik Hargunen Dunspeirrin Dupapn Durgg-Gontag Earth's End Eryndlyn Fardrimm Fluvenilstra Fraaszummdin Gatchorof Giant's Chalice Gracklstugh Guallidurth Holy Mother Cauldron Iltkazar Kuragolomsh Labyrinth Llurth Dreir Looblishar Lorosfyr Maerimydra Mantol-Derith Menzoberranzan Nuur Throth Oaxaptupa Oghrann Ooltul Oryndoll Reeshov Rringlor Noroth Rrinnoroth Sharnlands Skullport Sloopdilmonpolop Sshamath Sphur Upra Tethyamar T'lindhet Throrgar Tomb Tapper Tomb Traaskl Thorog Undrek'Thoz Wormwrithings YathcholDungeons in the Underdark
A “dungeon” is traditionally located underground, and no part of
the Underdark fails to qualify for the term in that respect. For
the purpose of adventuring in the Underdark, a dungeon is any
locale or extended area that offers the possibility of adventure,
danger, and treasure. By this definition, the Underdark contains
literally hundreds of dungeons. A few of the most infamous or
dangerous are described below.
Fortress of Gurzz'oth Irean Bridge Raval Spire Sorath-Nu-Sum Vaticos Rootstalk Citadel of the Fiendish Slayer Vault of Conjured Madness The Tumulus House of Dark Consumption Philock Drowned Multum Gduar's Garden Shape of WaterMagic of the Underdark
The Underdark eclipses nearly all surface-world locations
in terms of the sheer power of its magic and
its alien and frightening psionics. Who doesn’t fear
the deity-channeled malice and might of Lolth’s clerics? Worse
yet are the mind flayers, whose psionic and magical superiority
over most other races is as terrifying as their sinister appetites.
Less well known, and therefore more mysterious, are the aboleths
of the Lowerdark, which harbor secrets of ancient lore
within their alien, unfathomable minds.
Beyond what is generally known or rumored, the Underdark
shelters a wealth of strange power and magic. The long-hidden
deep Imaskari still know spells that leveled kingdoms in agespast. The gloamings and the slyths have abilities that few intelligent
creatures (even other Underdark races) understand. And
finally, there is the whispered rumor of node magic—a secret
lore that allows those with the proper training to channel power
from the earth itself.
Lore of the Underdark
Myriad are the paths to power, as the old archmages like to say,
and the Underdark is home to at least as many variant types
of magic as the surface world. Circle magic, rune magic, and
Shadow Weave magic all have their practitioners in the RealmsBelow. Cooperative circle magic is favored by the grimlocks of
Fingerhome. By combining their magical strength, a handful ofspellcasters may accomplish things together that even the most
powerful of their fellows could not dream of achieving alone.
Rune magic is favored by the duergar, particularly in the Underdarkcity of Dunspeirrin. And the Shadow Weave—the pattern
formed by the negative space between the Weave’s strands—is a
secretive, shadowy magic that has gained many converts in the
Underdark, including the kuo-toa of LoobliShar.
Psionics are even more widely practiced in the Realms Belowthan they are on the surface. The primary practitioners of such
powers are the duergar, the illithids, and the aboleths.
The Underdark also offers one other variant kind of magic
that is, for obvious reasons, available only below the earth. This
form of power is called node magic.
Faerzress Node Magic Portals of the Underdark