The Underdark

A vast network of underground tunnels and caverns, the Underdark sits below the continent of Baelor on Gaia. It is home to many Mindflayer, Duergar and Drow cities, and was the ancestral home of the Gith and the Gnomes (some Gith and deep gnomes continue to live in the Underdark, most enslaved by the Mindflayers or Drow). Creatures big and small call the Underdark home - it is one of the most dangerous place to traverse on Gaia. Most direct entrances into or out of the Underdark can be found within the Endless Peaks or the Broken Expanse, though a few others may exist outside of those locations.

History of the Underdark: Timeline
Untold BFA: Dais and the other light gods cross over from the celestial plane, and Dais destroys the elemental titans, using their essences to create the prime material, elemental and other planes

10,000 BFA: The dark gods cross over from the abyss, starting the Celestial War. After hundreds of years of war, Dais banishes them to the 9 Hells, though he and the light gods are banished back to Celestia as well. Life begins to recover, and civilization slowly begins to form. The humanoid races (humans, dwarves, halflings and gnomes) begin to colonize Baelor. Scalar is ruled by dragons, both chromatic and metallic. Fjordland is ruled by Tuvoc and their dire creatures. Orcs and Goblins spread throughout Arcos, their native continent. Kalzan’s vast desert is ruled by efreet and djinni, who constantly fight with one another for territory and slaves. The Vedalken begin to colonize Solara, forming small tribes that eventually turn into kingdoms. The races of the Underdark are enslaved by the mindflayers, whose vast empire stretches across the Underdark, ruled by elder brains all controlled by the Prime Brain. They enslave the deep gnomes, gith and duergar.

5868 BFA: After the War of the Elves briefly rages throughout the Everglenn, the defeated dark elves retreat into the Underdark to continue their malevolent ways. The dark elves encounter the Mindflayer empire, and begin to wage war with them. The mindflayers and their many slave races hold the upper hand, but the dark elves (now calling themselves Drow) carve out a niche for themselves in the southeastern corner of the Underdark.

4200 BFA: In the southwestern Underdark, the Duergar become the first slave race to successfully overthrow their Mindflayer masters. They begin to carve out their own small kingdoms, however they rarely have any sort of centralized power.

3100 BFA: An unnamed gith manages to kill the Prime Brain, upturning mindflayer society. Elder brains begin to vie with one another for power, using their mindflayers to wage war with one another. The empire crumbles, and while mindflayer cities are still common throughout the Underdark, the drow become the dominant power in the eastern Underdark.

3000 BFA: After years of fighting for freedom and escaping the crumbling mindflayer empire, many gith and deep gnomes flee the Underdark in an event known as the Exodus. The deep gnomes create underground cities throughout Baelor, eventually becoming the surface gnomes that assimilate into society. The gith flee the Underdark through the Broken Expanse, creating small settlements there as they slowly adapt to light and life on the surface. Many deep gnomes and gith remain enslaved by the mindflayers, drow or Duergar.

2500 BFA: The First Breach occurs when the Drow return to the surface to overthrow the elves of the Everglenn. Though they make considerable progress, destroying the elven capital of Izlandar, the surface elves eventually force them back underground. They begin to send select groups of elven scouts underground to monitor drow activities.

400 BFA: The Second Breach begins, as the Drow once more rise to the surface in an attempt to destroy the elves of the surface. However, the elves are well-prepared this time, and the breach is easily overcome. The drow retreat underground in defeat.

882 AFA: The Third Breach begins, as drow forces this time rise out of the Broken Expanse. The surface elves are caught unaware, and their capital of T’Avar sustains extensive damage. Forces from the Crimson Empire come to their aid, and together they drive the drow out of the Everglenn and back to the Underdark. This begins a strong alliance between T’Avar and the Crimson Empire.

1000 AFA: The Wasted Wanderers' adventure begins.