FifthColumn's Curse of Strahd
Durst House, colloquially called Death House, is a long-abandoned and significantly haunted townhouse in the Village of Barovia. Once the home of the well-to do Durst family ( Gustav, Elisabeth, Rosavalda, Thornboldt, and Walter) as well as their servants, the house was host to a diabolical cult who tried to entreat the favour of Strahd but were denied.
The Outlanders arrived at Durst house some centuries after the family and other denizens had died. They determined that the house has its own malign sentience which tries to draw in the unsuspecting and to consume them. The house not only is home to various undead spirits including the Dursts, but actively summoned fire, scything blades, and swarms of vermin to impede the escpae of the Outlanders, and nearly succeeded.
At the time they left the property, the outlanders believed that the ghoul and ghast cultists, the specter nursemaid, the animated armor guardian, and the shambling mound in the catacombs had all been lain to rest. However, the ghosts of the children remained, as did the wicked devices of the house itself.