Koriszegy Keep and the Rodemus family
by Mike HarveyHere is one possible unification strategy.
The Koriszegy and Rodemus families are one and the same. One is the Thyatian name and one Traladaran. Perhaps after the fall of the Koriszegy family the lone surviving female heir (who own the castle) married into Thyatian nobility and change her surname. Since no Koriszegys remain, over time the names became conflated. Lands and ruin are now known as Rodemus family (especially by Traladarans eager to tar the newcomers)... the accidental linguistic association between rats and family name has added to the confusion, so that most folks now assume it really was the Rodemus.
On top of that, the Rodemus briefly tried to clear and inhabit the keep shortly after coming into possession if it. That didn't end well, and a brief outbreak of lycanthropy and bloody tragedy completely cemented the families' dark reputation. The Rodemus don't speak of it and even the younger Rodemus believe a shadow hangs over the family. Perhaps the devout family elders encourage the misconception as a warning, so that it doesn't happen again.
What is the truth? Is it vampires or wererats? Actually it is both, and probably fiends too. The Koriszegy family was tainted by lycanthropy and evil long before the pact that destroyed their home. The undead and wererats dwell together, for they are family, and the clan elder is probably the only Nosferatu-Wererat (devil swine?) on the planet.
Locals don't know what is down there. .. rumors are confused and conflicted, and tell of other monsters as well such as goblins and Thyatian assassins. Old timers like to argue about them in the local taverns. Many feel that the rumors of various lycanthropes and undead have more to do with Traladaran fears and legends than reality; after all werewolves and vamps lurk behind every tree, and who really takes them seriously? It's the go-to explanation for anything unknown. Still, folks hurry home after dark and shutter their windows, just in case. And nobody goes near the keep. Because the only thing anyone can agree on is that curious trespassers are never seen again.