Research About Limbo and the Plaguelands

There is much scholarly and literary work that concerns the Plaguelands. Since the Great War, the Plaguelands have been a source of fear and danger for much of Greater Sembara, a wilderness of monsters and strange magic. Many heroic epics depict journeys into the Plaguelands, and many historians catalog the terrors and curses that have emerged from them.

Most interesting is the obscure work of the dwarven mathematical cosmologist Harbek Ferrystone. Harbek lived in Rinburg, a trading town in the Barony of Aveil, and published his most notable work, Planar Tides in Relation to the Dangers of the Plaguelands in DR 1703. In this work, he noted that the dangers of the Plaguelands seemed to wax and wane over time, with bursts of extreme danger (e.g., the Blood Plague, the Cursed Cold) punctuated by periods of quiescence. He then proceeded to develop a mathematical theory of planar tides, which Harbek claimed could be used to predict the degree of danger of the Plaguelands.

His work focused on a description of planar movement that involved three cycles: planar drift, operating on decadal timescales; planar tides, operating on monthly timescales; and planar flows, operating on variable timescales and affecting the direction and strength of connections. In his analogy, the linkages between planes could be thought of like a mill-dam feeding a waterwheel. The slow silting and shifting of the riverbed, which raises or lowers the whole channel, is planar drift; the opening and closing of the sluice gates to meter the wheel’s motion is planar tide; and when a storm sends the river over its banks, sweeping wheel and dam alike away, that is planar flow.

Specifically, Harbek sought to predict the strength of the connection between Limbo and the Material Plane that he believed influenced the Plaguelands. He claimed that planar outbursts, leading to terrible dangers like the Cursed Cold, could only occur when planar drift and planar tides coincided to bring Limbo and the Material Plane into close alignment. At these times, though a planar outburst was not guaranteed, the conditions were right for a particularly strong planar flow to “spill the banks”, so to speak.

His mathematical treatment of this was complex, for neither planar drift nor planar tides occurred on strictly regular cycles. Nonetheless, he was able to accurately predict both the major spillovers and minor events, sometimes even within the month. He was even able to warn, in advance, of a period of vulnerability in DR 1709, during which, indeed, a series of unseasonable thunderstorms during which acidic oozes fell from the sky swept from the south. But with warning, the damage was far less than it could have been.

However, Harbek’s mathematical predictions were discredited in DR 1720, when the War of the Ashen Horde broke out in the March of Andonne and the Refounded Alliance of Aurbez at a time when, according to Harbek’s predictions, Limbo was distant from the Material Plane and no planar outbursts should have been possible.

Subsequently, Harbek’s work fell into obscurity. Nonetheless, it highlights the possibility of a deep connection between the Plaguelands and Limbo.