The Archive Discovery
The First Survey

It was found by accident. Renovation crews working in the Bastion's upper levels - repairing a wall cracked by the tremors of the Planemeld - unsealed what appeared to be a disused temple room. The masonry within was older, smoother, and cut with a precision no one in the Bastion had ever seen. At its centre stood an ancient Ayleid gateway. It predated the fortress by centuries.
Behind the wall: a sealed passage leading to an ancient gate. Beyond it - Abagarlas. Not collapsed. Not buried. Intact. The ruins sat in perfect darkness with the patience of things that do not need to breathe. Valyria recognized the stone. She had walked on the same black rock in Coldharbour, on the Shrouded Plain, during the assault on the Planar Vortex. Molag Bal's influence was still in the walls after thousands of years.
Three scholars and four guards made up the first survey team. They mapped the passage in one night. It was not long - maybe forty metres - but nothing about it was right. The stone was warm. There is no reason for stone that far underground to be warm. The smell of ozone thickened as they climbed. At the upper end, the keystone was intact, but the mortar around it had turned to powder, as if time ran faster inside the seal than outside it.
Beyond the Seal

Everything the clan knew about their home changed in a single night. They had not simply inherited an old fortress in Blackreach. A sealed passage in their own library led through a gate to the ruins of a temple devoted to their patron's oldest enemy. And that passage was older than either structure.
Valyria went through the keystone first. She knew the ruins on sight - not from books, but because she had walked on the same stone in Coldharbour. The blackened rock, the faint violet glow in the walls, the way sound moved as if the air did not want to carry it. Abagarlas was not just old. It was still connected to the realm of the Prince who had claimed it. Residual, faint, but present. The kind of connection that does not fade with time because time is not what maintains it.