Chauntea

Centuries ago, the world lived in relative harmony, with the kingdoms of man keeping order between the many races of the surface while protecting them from the evils of the Underdark, the world below the surface that was filled to the brim with endless monstrosities that threatened the utopia forged by humanity. One day, humanity completely disappeared, taking with them the vast knowledge required to keep the forces of the Underdark in check. The surface was overrun in days with the various races of the surface either enslaved or scattered as the new world order took hold. Now, the surface is ruled over by the cruel alien minds of ancient aboleths, controlling mind flayers, paranoid beholders, and powers long forgotten like the terrifying dragons, massive giants, deceitful fey, mindless automatons, and decayed liches.   Left with no other options, the races which once called Chauntea home submitted and assimilated, though pockets of resistance persist despite the overwhelming opposition. These fighters rely mainly on guerilla tactics to fight wars or otherwise depend on secrecy and subterfuge to accomplish their goals. Those few forces that wage open warfare on the new rulers of the world do so with the remnants of humanity's advanced technology and knowledge. Many fled into the now mostly-vacated Underdark where they had to contend not only with the monstrosities of the darkness, but also the corrupted remnants of former slaves to the new rulers of the planet. Others survived largely unscathed in small, well-hidden pockets and alcoves where they developed separately from the rest of their kin.   Finally, those who lived under the rule of their new masters had wildly divergent experiences. Some were left largely alone, like those who lived under the aboleths and giants. Some were treated with cruelty and oppression, like those under the beholders and fey. Those under the control of the mind flayers, dragons, and liches were turned into cattle, serving as food and fodder in their wars. Finally, under the mindless constructs of ages past, all organic life was actively eradicated, making them one of the most contested powers in this new world order.   On top of these factions that now rule the planet are the many artifacts, entities, locations, and phenomenon that humanity had contained and kept separate from the rest of the world to maintain the status quo. Without the knowledge to control and contain these oddities, the surface world is vulnerable to their power and influence, amplifying the oppression and terror of everyday existence a thousand fold. While one might live a prosperous life under the thumb of an apathetic giant, it may still end in blood at the hands of some deranged orc with a sentient sword, demonic cultists who need a sacrifice, or random portal that shunts someone into a nightmarish demiplane.