SCP-X is an extra spatial shell mound with various underground regions, and it is primarily made from packed layers of precosmogonic bone. Embedded carvings and rudimentary script drafted on each bone match the stanzas found in the poem Völuspá. Angular ribs demarcate the circular boundary lines of SCP-X, which are 15m in circumference, while a sternum stairway descends and terminates at a hermetically sealed vault made from a flattened skull, 10m in total height. Radiocarbon dating suggests SCP-X's constituents range between 15,000 B.C.E to 1200 C.E.

SCP-X-01 are skinless, amber-red humanoids who unanimously believe that the world outside of SCP-X has ended. As the lower regions of SCP-X are devoid of light source, save for biolluminscent fungi continually-grown from makeshift “gardens”, SCP-X-01 instances emit a form of precosmogonic radiation that map structures and allow for navigation. It is analogous to ground penetrating radar.

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