The sealed Manor was located near the City of Tens on the other side of The Forest of Athmenra and the Twisted Desert is surrounding the Castle on the other side of the lush green woods and used to belong to Lord Nasher. Nasher was tyrant who called himself King of Argannon, who later turned out to be Mephistopheles himself however, when Nasher was defeated the Manor was kept open for the public and is said to have multiple floors with rooms, hallways, rich baths, libraries, dungeons and an impressive throne room.
Like this it stayed until the end of the Overlord. When the nearby land crumbled the castle was closed up and no one has been able to find a way in except from small corridors here and there that either are dead ends or leads out on balconies with the view over Nasher's Park. The former invasion of purple worms in and underneath the Pariah Cathedral was suspected as having contributed to the demise of the land one rumor goes.
The Manor used to be connected to the Ruins of Argannon however through the old catacombs but since the Shift due to the Overlords death the tunnels were destroyed and cannot be reached from the old ruined city.
Many debated to who the Mansion truly belonged. Many tried to claim it as their own however through the reign of the now retired Queen Ta'hyen Nyarr of Argannon (which some still dispute not ever being an actual Queen) it is more commonly known that nobody owns it.
The Park is still open to the public if one ventures through the old sewer system, and within the park one can find the old Pariah Cathedral and transitions over to Bloodplains. Also it is rumoured there is a secret room located somewhere within the Cathedral and some of the old Manors balconies can still be reached through small passages from the courtyard of the manor.