Atyersus (“Tower of Warning” in Kyranean) is the sister fortress of Attrempus. It was founded in 2157 by Seswatha and other Gnostic survivors of the Apocalypse. Atyersus is the primary stronghold of the Mandate. Atyersus had been built in the manner of the Ancient North, whose architects had known nothing of arches or domes. Her inner galleries were forests of thick columns, their ceilings obscured by canopies of darkness and smoke. Stylized reliefs sheathed every pillar, providing the shining braziers with too much detail.