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Maldin's Greyhawk

Greyhawk's Underdark

by Denis Tetreault
Version 2.10

The idea of a special "world beneath the world", a dark, mysterious place isolated from the surface world of the player characters and filled with natural wonders and ancient evils, was first introduced to D&D players and DMs as the D-Series of modules (D1 Descend into the Depths of the Earth, D2 Shrine of the Kuo-Toa, and D3 Vault of the Drow) first published in 1978, and later reprinted in 1986 as the GDQ1-7 Queen of the Spiders supermodule. This new subterranean world was based in the World of Greyhawk. Since then, much has been written about this "underdark" realm, both set in specific worlds (such as the Forgotten Realms) and as generic writings, as numerous adventure modules, magazine articles, and hardcover rulebooks for every edition of D&D since. The popularity of the setting even spawned a series of highly popular novels by R.A. Salvatore about Drizzt, a drow ranger from the Forgotten Realms.

This section of my website will strive to present material about Greyhawk's underdark, sometimes referred to as "DeepOerth". The material here could also be easily adapted by DMs to fit into any campaign world they choose to use.

The Ancient City of Khor

The ancient city of Khor is found within a very large cavern located at hexes O2-P2/23-25 on the "Underground Passages" map that can be found in the adventures D1 Descent in the Depths of the Earth, and D2 Shrine of the Kuo-Toa. A "Free City" inhabited by all manner of creatures, it can serve as a location to be explored by adventurers, or as great jumping off point for starting an underdark-based campaign without the complicated politics of starting PC's (particularly non-drow) in Erelhei-Cinlu.

A Regional Survey of Greyhawk's Underdark

This very special map, a layered PDF, covers the underdark regions beneath the Yeomanry, Hool Marsh, Tors, Hellfurnaces and surrounding areas in the southwest Flanaess. The map, and accompanying descriptions, ties together the D Series of TSR/WotC adventures (later published as the GDQ1-7 Queen of the Spider supermodule), the Night Below boxed set supermodule, and the 1st Edition Dungeoneers Survival Guide into a single massive DeepOerth campaign setting.

Dragonsfoot Collaborative Project: Mapping the Depths of the Earth

This is a Dragonsfoot community project discussed at the Collaborative Project: Mapping the Depths of the Earth forum (originally proposed by PapersAndPaychecks in May 2005, and kicked off by Gnarley Bones, in July 2006) to detail all of the remaining areas on the map provided in D1 Descend into the Depths of the Earth, and that were not described in the original D-series modules. The last compilation of the project, edited by Iain_IF in 2008, can be downloaded as the "Encyclopedia Subterranica" here. Check back for updated versions as the project proceeds. Eventually, a finalized document will be available here and on the Dragonsfoot website. As time passed, it became clear that a continually updated compilation volume was not tenable for a variety of reasons, though updates of individual encounter areas could be accomplished, so I created this page. Below is a new index map of the area. DM's can click on an encounter area on the map (or the chart below) to view a PDF of the single encounter description, if a completed one is available. Hovering over the encounter areas with your mouse in the index map below will bring up pop-up text with the name of the encounter. For the incomplete encounters, check the compilation volume where some can be found, others were never released. I will continue to attempt to get those out, if I have materials from the original authors, or I can get in contact with them.

For a high-resolution (1500x2166) version of the index map suitable for printing, please click here.

The collaborative project is indeed a massive undertaking, consisting of contributions from 20 different authors. The current state of the project is summarized below. Completed encounter areas are available as part of the compilation volume, and will become available as separate files accessed off the index map above (by clicking on each corresponding map location) and from the chart below, as the individual PDFs are being created. Other encounter areas will become available as the authors complete them. Check back to see how things are going.

# of Hexes
Encounter Name Creator Status
001 B/9
Trading Post of the Dead, Dying, Damned, and Doomed Dwarves! Predavolk Complete
002 B/30-31
The Duergar Redoubt Eldersphinx Complete
003 C/19
The Duergar Guardpost SoulCatcher78 Complete
004 D/3
Drow Checkpoint Gary Gygax Module D1
005 E/15-F/16
The Moaning Chasm SoulCatcher78 Complete
006 F/35
Obsidian Pool of the Fallen Star jmidd Need Map
007 I/18
Bugs Iain_IF Complete
008 I/25
Purple Worm Warren Michael Sandar Incomplete
009 J-K/31
The Repository of Lost Souls Xiuhcoatl "Xi" Incomplete
010 K/4
The Captive Pech Istarlome Complete
011 L-M/19
The Trading Grounds Eldersphinx Need Map
012 M/12
Mind Flayer Spy Post Gary Gygax Module D1
013 N/38-39
Kuo-Toan Town wbeatty Incomplete
014 O/10
Cleanup Crew Eldersphinx Complete
015 Q/18-19
The Caverns and Warrens of the Troglodytes Gary Gygax Module D1
016 Q/32
Hidden Shrine to the Elder Elemental God wbeatty Incomplete
017 R/9
Wererats' Warren Eldersphinx Complete
018 S-T/17

The Ghoul Warrens (map held by ghouls and ghasts
in D1 leads back to here)

Marco Complete
019 S/27
Stone Giant Mining Project thenraine Complete
020 T/40
Shadows in the Darkness Runecrow Complete
021 U/13-14
At the Gate of Da-mur-shou (A Mind Flayer Outpost) Runecrow Need Map
022 W/22
Mice in the Lab Maze Disjected Complete
023 W/27
Thoopshib's Barge Crossing Gary Gygax Module D2
024 X-A2/43-45
The Forsaken City of Naavros Eldersphinx Need Map
025 Y/26
The Dread Sinkhole Eldersphinx Need Map
026 Y/36
027 Z-A2/35
The Secret Garden wbeatty Complete
028 A2/20
The Fire Giant Ambush Istarlome Complete
029 A2/31
Svirfneblin Prospecting Claim Gary Gygax Module D2
030 B2/14
031 B2/24
Svirfneblin Trading Post Elfdart Complete
032 C2/20
The Fire Giant Lair Istarlome Complete
033 E2/24
The Lava Fissure Istarlome Complete
034 E2/43
035 F2/29
Grotto of the Morkoth Eldersphinx Need Map
036 I2-J2/34-35
037 I2-J2/47-48
The Fungi Caverns Gnarley Bones Incomplete
038 J2-K2/26-28
The Svirfneblin Stronghold Istarlome Incomplete
039 L2/31
Sanctum of the Absent Mage Eldersphinx Complete
040 L2/41-42
Shrine of the Kuo-toa Gary Gygax Module D2
041 M2-N2/18
042 N2-O2/51
The Drowad Caverns Papers and Paychecks Complete
043 O2-P2/23-25
The Ancient City of Khor Maldin Complete, future
website expansion
044 Q2/49
Gateway to the Vault of the Drow Gary Gygax Module D3
045 R2/28
The Forbidden Cavern Maldin Incomplete
046 R2/47
Grotto of Silussa and Belgos Gary Gygax Module D3
047 S2/30
The Smugglers Elfdart Complete
048 S2/33
Beware the Lord of Eyes grodog Complete
049 U2/32
White Goblin Ambush Elfdart Complete
050 U2/48
Black Widow Guardians Gary Gygax Module D3
051 W2-X2/27-28
  Papers and Paychecks Incomplete
052 W2/31
053 W2-Y2/44
The Chasm of Deadly Breath Eldersphinx Complete
054 X2/37-38
Realm of the White Goblins Elfdart Incomplete
055 Y2-Z2/54-57
The Vault of the Drow Gary Gygax Module D3
056 Z2-A3/24-25
(Isle on the Sunless Sea) Papers and Paychecks Incomplete
The Ursinians Terry Need Map
Escaped Slaves Disjected Need Map
The Brazen Tower Eldersphinx Need Map
random encounters Bodanay


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This page last modified on August 2, 2021