The Orthen Oubliette is a prison designed by the Nodon dragonkin to contain Raksha, the Shadow Colossus. It is located underground in the south-west portion of the Anachronia south-east ruins. It is overseen by The Keeper, who guards the oubliette as well as maintains the containment cycle of introducing vats of shadow anima to keep Raksha alive and dormant.
The cell itself rests deep underground to prevent the shadow anima stored there from affecting living things on the surface. The oubliette includes a hologram projection system for the Keeper to broadcast information to visitors, as well as also utilising a security system outside of the main containment chamber that uses a hydraulic lock mechanic as a backup to keep Raksha in place during an escape attempt. This security feature is activated in the Raksha fight during the final phase of the encounter. Raksha itself is shackled by large chains made from dragon metal, which go through the walls; part of this chain can be seen in the xolo city.
During the miniquest, Laniakea asks the World Guardian to help her investigate the ruins leading into the oubliette. She is unable to survive the shadow anima, and leaves the area to be explored by the World Guardian alone. They instead find Zaros conversing with the Keeper, who then shows both them and the Keeper a vision of Raksha's past, before stealing a vat of shadow anima, thereby breaking the containment seal and schedule, and waking Raksha.
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