At the southern tip of the Seguk landmass, a belt of polar wasteland tips the massive continent. Due to the poor weather, lack of resources, and abundance of easier land to expand upon - this has become a barren, forgotten portion of the world. Here where the weather and predators actively work against life, the home of Tacitus Athanasius sits. No one could possibly find this region desirable except the Mistress of Assassins, Shadow Nighthunter, and her cadre of assassins. They use the unforgiving land to brutally hone their skills as apex predators of House Excidium. In the Twilight Cathedral, they pay homage to their craft: learning weapons, honing survivalist skills, employing deception and subterfuge, and parting way with the part of their souls opposed to murder. Here, nestled into the Bernese Barrens - a natural Tundra - sits the Twilight Cathedral and Tacitus Athanasius.

The building itself is reminiscent of the Silent Death Citadel as it contains an elaborate main hall, a ritual chamber, dormitories, training halls, a library, a menagerie, medical center, an armory, and a docking bay with an exterior landing pad for incoming and outgoing flights. It does not have extensive technological modifications or have a ‘modern’ feel. Every inch of the building has been shaped with a purpose and could be described as beautiful strength. It has foregone metal and plastics for rich, warm woods and massive, complex stone. Each shows vibrant color and is unlike any other piece within the building. While the climate and training may be harsh, this is much a retreat for active members of Tacitus Athanasius as a Forward Operating Base for House Excidium.