At some point in the late 13th-early 14th century, a convict was voluntarily lowered into a black pit that had been discovered in Kokorin Forest in exchange for clemency from King Ottokar II.
His task was to report on what he found down the pit, but he returned to the surface 30 years older and his mind destroyed, speaking of the horrors he had witness down there before dying. (COMIC: Herald of Madness)