Contagion of Shadow Affects Villages in Volsin Wood - Archduchess Missing

Dateline: Still Waters, West Volsin County, Duchy of Elkur - 4 Bretranel's Month: The Varangian Guard today released a report on behalf of Gerom, Duke of Elkur, alleging that a 'significant incident' had occurred in the otherwise unremarkable Volsin Westwoods, poisoning the Feylween river and causing unexplained but significant damage to the village of Still Waters. The death toll and the fate of nearby Thistlehill is unknown, but reports from the region also confirm that the Archduchess of Zauzet, Coldhorn and Adevarul is indeed missing; she has not been seen in town, nor with the rest of the Baron Council, nor at her stronghold, nor in her recently inherited and controversial land holdings in central Naarod.
The Varangian Guard officially had no comment, suggesting that the events might be unrelated if she has fled from the impending damages judgement assessed on her holdings, estimated at more than 20 million in gold for the damages and deaths caused by the Orc Incursion late last year that was determined to be a false flag attack by the Duke himself. The Duke is also missing, and authorities fear the two may be planning an attack on the Autarch or the City from an extraplanar location, though no proof of this rumor has been identified.
Related or no, the contagion of shadow is centered somewhere in the Volsin Westwoods; the Archivists guild has extensive information regarding the lich, Uhl-Kal-Totten, who terrorized that region several hundred years ago before his rule and (un)life was brought to a swift conclusion by the Party of Seven, of particular interest as the origins of the Duchy of Zauzet go back to the King of Naarod in those days awarding it to the wizard in that party, Rakkir's familial ancestor. Some have speculated that rather than an ancestor, Rakkir himself has actually sustained his life well beyond the normal span for a human, and occasionally staged a death and inheritance to maintain the Duchy himself, all these years.
Nevertheless, the various frauds and deceptions of Duke Rakkir have been financial and mundane in nature, and no creeping darkness of this sort has been seen in a thousand years, and never in the Prime Province of Khazig, so it is unclear if this connection is merely a coincidence; the Archivists Guild continues to peruse the records available to us to clarify the connection, if any.
The Duke of Elkur sent a coterie of soldiers to investigate the contagion, but they have not checked in or returned with any answers in over a week. Local reports confirm that the contagion is spreading rapidly and it is not known what efforts might be effective to stop it, nor exactly what effect the creeping darkness has on sentients; it has a debilitating effect on wildlife, evidenced by the stream of dead fish flowing downriver of the contagion. Upriver, closer to the source, the water is said to run a silky black, with inexplicable weight but no grittiness or sediment. Torches are said to be overwhelmed there in moments and even sunlight seems unable to penetrate into the heart of the forest. It would appear as if the plane of shadow or some other lower plane of negative power, such as an abyssal or infernal plane, is spilling into our material plane.
The military response is hampered by the lack of solutions to the issue, though the Varangians and the Autarch stand ready to address any military threat, should one arise; in 10,801, the creeping darkness in Venen covered an entire mountain, from which a spectral army charged out and decimated several communities before finally being put down by Imperial Witches specializing in undead-slaying, and three divisions of Kazigiri Tigers. Other details between the two incidents suggest they aren't related, as the spectral army was later proven to have come from a major conspiracy of cultists of Orcus who were relentlessly exterminated and, should any still exist, do not have the numbers to pull off another mass conjuration event. The magical signatures are not conjuration at all in the Westwoods event, but rather a physical contagion with a planar involvement.
More bulletins will be released as additional information is gathered; at this time the only communities affected are Still Waters and Thistle hill, with combined populations fewer than 200 persons, but their fates at this time are unknown.