Location from Arknights by Hypergryph
The thing beneath the dead city — a Predecessor device discovered under Chernobog whose power catalyzed industrialization, rebellion, and transformation, and which still holds secrets about Terra's alien origins.
The Sarcophagus feels wrong — not dangerous in the obvious way of a weapon, but wrong in the way that a door to somewhere you shouldn't go feels wrong. The energy it emanates powered Chernobog's rapid industrialization but also attracted the attention of forces (Kal'tsit, Reunion, the Ursus government) who understood what it truly was. The Doctor was stored in it during their three-year stasis, and Mephisto was transformed into an inhuman creature after entering it. It is a Predecessor artifact — proof that the alien race that created Originium left technology buried across Terra that modern civilizations are only beginning to uncover.
An ancient device of clearly non-Terran origin, buried deep beneath Chernobog's mining infrastructure. Its design is alien — smooth, geometric, and made from materials that don't match any known Terran manufacturing. It emanates energy that can be felt before it's seen: a low vibration that makes bones ache and thoughts scatter. The chamber containing it is vast and cathedral-like, carved by the mining operation that uncovered it.
Also known as: The Predecessor Device, The Ancient Device