Scorched Plague

The Scorched Plague was a major pandemic affecting the Appalachia region in the aftermath of the Great War. The plague originated from a research project conducted by West Tek in cooperation with the United States government. The goal of Project Scorched was to replicate the physic and mind control abilities naturally found in Psykers using the Scorched Fungus, found naturally in Appalachia. The test subjects soon developed limited physic powers, but their powers greatly expanded when the nuclear conflict unleashed massive amounts of radiation in the region. These subjects, heavily mutated in beings called Scorchbeasts, escaped the facility and fled underground.

The Scorchbeasts developed a linked hive mind, and discovered they could bring others into the hivemind by infecting them with toxins emitted by the mutated Scorched Fungus. The Scorchbeasts unleashed the toxins across Appalachia, severely depopulating to the point where no humans remained until Vault 76 opened in 2102.

The humans within Vault 76, unaffected by the radiation and mutations of the outside world, maintained a limited resistance to the Scorched Plague, enabling them to fight back against the Scorchbeasts. The activation of three dormant nuclear missile silos destroyed the Scorchbeasts' underground lair and rendered them extinct.

The effects of the Scorched Plague remained however, cutting off Appalachia to those not from vaults for another two hundred years, until the last remnants of the fungus were destroyed.