Nidavellir

Nidavellir, also known as "dark home", was the third layer of Ysgard. It consisted of a series of underground tunnels and vast warm caverns. It contained numerous divine realms and was the location of two major warring realms: Nidavellir and Svartalfheim, which was believed to be the divine realm of Eilistraee.

Geography
The entirety of the layer was underground. Its tunnels, chambers, and caverns were kept warm by hot springs and geysers, which provided ample heat to sustain the native vegetation, which consisted of woods that required no sunlight to grow.

Notable Locations

 * Brassberg, realm of Hlal.
 * The Cavern of Rest, realm of Marthammor Duin.
 * The Merciful Court, realm of Sharindlar.
 * Nidavellir, a realm of dwarves and gnomes with an unclear ruler.
 * Svartalfheim, a realm of drow that was believed to belong to Eilistraee, although its true power was not known for certain, as rumors persisted that it belonged to Erevan Ilesere instead, or some other power.

Inhabitants
Most of the layer was inhabited by dwarves and gnomes who, despite their natural animosity towards each other, worked together in their forges and crafts. The drow inhabitants of Svartalfheim were not evil like their counterparts from the Prime Material plane and wished only to be left alone.