The planet Tenebrae in the Zuran Expanse lives up to its name. In the gloom beneath perpetually darkened skies, the all but lifeless wastes hold the ruins of two civilizations These ruins draw treasure seekers and archaeologists, but they don’t easily give up their secrets.
Tenebrae was a terraformed world and once home to thousands of colonists. A few large surface craters suggest this civilization was destroyed by meteor impacts and the nuclear winter that followed. This is believed to have been a purposeful assault rather than chance encounters. Most life above the unicellular level was destroyed.
Sometime later, the enigmatic zurr arrived. As on every other world with a zurr presence, only what appear to be ritual sites have been found: Three labyrinthine structures the size of small cities are evenly spaced along the equator. They’re made of a rock-like material with the appearance of basalt not found elsewhere on the planet.
Artifacts are found within the labyrinths, seemingly at random: small, nonrepresentational sculptures, pieces of the elaborate ceramic masks the zurr seem to wear (seen in the holographic images with the appearance of mid-reliefs embedded in the walls), and oddly, personal items the previous human civilization the zurr or someone else must have excavated from older ruins.
These trinkets can bring a few credits in the right markets, but the most valuable of the Tenebraean artifacts are the obsidian pentachorons. These items (or perhaps their 3 dimensional shadows) are found ensconced in rare alcoves in the walls of the labyrinths, where they have the appearance of glassy, black pyramids. When held by a sapient being the pyramid takes on the appearance of a 4-dimensional solid rotating through 3-dimensional space. The rate of rotation of a pentachoron changes in the presence of a
hyperspatial node. Psi sensitive individuals holding a pentachoron hear a multitude of whispering voices. The objects are resistant to damage, but they can be destroyed—though only utterly. No one has ever succeeded in fragmenting or shattering one.
The pentachorons and the other treasures are zealously guarded by short humanoids called “skulkers.” Little is known about them, except that they appear to inhabit subterranean warrens beneath the labyrinths, they shun bright lights, and they are utterly hostile to other species.