The Underdark is a literal underworld to the surface world for the Dungeons & Dragons roleplaying games. It is a vast subterranean network of interconnected caverns and tunnels stretching beneath entire continents.
The Underdark is a strange alien landscape populated by bizarre creatures and ancient races, nearly all of whom are hostile to surface-dwelling life. The Underdark is featured prominently in the World of Greyhawk (where it was first introduced).
- Capital: None
- Population: Unknown (aboleth, cloaker, drow, duergar, illithid, quaggoth, svirfneblin)
- Government: City-states, each with different government (autocracy, magocracy, matriarchy, monarchy, theocracy, and so on)
- Religions: Varies, usually racial pantheon
- Imports: Armor, food, slaves, timber, weapons
- Exports: Armor, exotic goods, magic, weapons
- Alignment: N, LE, CE
The Underdark is extremely dangerous, especially to those not native to it. There are the usual dangers associated with caverns: claustrophobia, occasional poor air circulation, and getting lost. There is no light except for occasional patches of fluorescent fungus; most Underdark inhabitants either have highly developed senses other than sight or have developed infravision before the 3rd edition of the game rules). Food can be extremely difficult to find, and much of the natural vegetation is poisonous. In the Forgotten Realms setting the Underdark is permeated with a magical energy the Drow call faerzress, which is used as a source of energy by the native plant life but which interferes with scrying and teleportation spells.
In addition to those dangers, the Underdark is also home to many predators and a wide array of races, most of which are hostile to other races. These races include:
- Drow (dark elves)
- Duergar (gray dwarves)
- Illithids (Mind Flayers)
- Lerara (Suel humans)
- Svirfneblin (deep gnomes)
- True ghouls
- Amalriv, male drow, chief tax collector of Erelhei-Cinlu.
- Belgos, vampire.
- Eclavdra of House Eilserv, drow priestess of Lolth (formerly of the Elder Elemental God, as well as Graz'zt).
- Edralve of House Eilserv, drow priestess of Lolth and former Slave Lord.
- Edylyn, an emissary from Erelhei-Cinlu currently on the plane of Acheron.
- Jalvan, male drow agitator in Erelhei-Cinlu.
- Llemual, half-drow artist and mage, possibly now the lich-lord ruler of an Underdark kingdom.
- Ool Eurts, drow sorcerer and artist.
- Pruuma the She-Bear, powerful female bugbear of Erelhei-Cinlu.
Features and settlements
- Lost Tunnel of Slerotin
- The Sunless Sea
- The White Kingdom
Specific prestige classes
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- Underoerth project on Canonfire!