The Pillar of Heaven
Gleaming white cylinders nearly ten thousand kilometers long, featureless save for gigayears of micrometerorite scarring. Five have been found so far - all in wide orbits around resource-poor and otherwise unnoteworthy stars.
Four of the five pillars actively broadcast simple, clearly artificial radio signals. These align with the typical contact beacon format of a loop of increasingly complex mathematical formulae on the 1420 MHz band. Should observers attempt to respond to this broadcast, the pillar will broadcast an extensive corpus of linguistic data. The language is precise, analytic, and obviously engineered for easy comprehension by automated translation software.
After the observer has transmitted a message containing any parts of the provided language, the pillar with switch to a loop of the following transmission:
DEFEAT OF ENTROPY! [past continual tense marker]
THOSE WITHIN ENDURE! [future continual tense marker]
GIFT WITHOUT PRICE! [emphatic statement marker]
ALL MINDS ARRIVE! [emphatic request marker]
Non-android individuals coming within 300m of a pillar will die instantaneously.
The pillars' message has inspired a fervent religious revival within the Expansion Sphere. Thousands of pilgrims attempt to reach them yearly, though few are able to make it through the corporate blockades of the five home systems. Common rumor on the ground is that the blockades are not for the prevention of mass suicide, but as a means of cutting off the only means of escape from a universe dominated by the twin forces of capitalism and entropy.
The reason for the fifth pillar's silence remains unknown.
The Scholz's Star Shellworld Builders
Scholz's Star is a red/brown binary dwarf system that passed within a lightyear of Sol (~52,000 AU) some 70,000 years ago, close enough to interact directly with the Oort Cloud. That'll be a problem in about two million years, but that's a problem for two million years from now.
It would have passed on as an otherwise mundane unique occurrence, were it not for the fact that the drone ship later sent to map the system found that it was inhabited. A total of 24 shellworld habitats (artificial planets built around planet-mass holes), ranging from 500 to 4000 kilometers in diameter orbit the two bodies in system, each with a resident population of baseline humans and terragen flora/fauna. Genetic and cultural drift over tens of thousands of years, plus the lack of inter-habitat transport, has radically diversified the population. All extant societies, at the time of discovery, were pre-industrial, though this analog extends only to technology and not to social beliefs, which vary widely.
No other traces of the Shellworld-Builders have been found. It can be assumed that they were not natives of Scholz's Star, due to lack of any planets that might have supported life and the requirements of their apparent technological advancement. Their motivation in building and peopling the shellworlds also remains speculative - they didn't appear to make any physical modifications to the abductees, nor any noticeably imposed cultural structures.
That the closest approach of Scholz's Star and the Youngest Toba Disaster and resultant human genetic bottleneck occurred within the same time frame has not gone unnoticed
An entity or group of entities encountered only by those conscious during hyperspace transit or aboard vessels with malfunctioning Caldwell Manifolds. As with all hyperspatial entities, it is impossible to observe outside of its effects on humans; no hypospace manifestations have yet been confirmed.
Humans exposed to the Bloat will form a sort of parasitic relationship with it. The early stages are marked by an increasing physical and mental lethargy and inertia, followed then by the gradual loss of food or water. Those effected will eventually become nonverbal, though interviews from subjects prior to total loss have included statements implying a group-mind shared between effected individuals and the Bloat itself, as well as advanced understanding of hyperspatial mathematics. This latter trait has made Bloat-linked subjects a valuable commodity across the Expansion Sphere, as with with right cybernetic links a fully parasitized individual is outclassed only by a dedicated Navigator in terms of astrogation abilities.
Occasionally, Bloat-linked subjects might undertake construction or artistic projects of unknown purport. These should be destroyed upon identification.
[OAI EYES ONLY]
Xenothreat [BLOAT] rival / enemy to xenothreat [GAUNT]. Mutual aggression between effected parties. Further research required. Further specimens required. Construction or artistic projects undertaken by affected subjects to be destroyed upon identification. Recovered subjects to be transported to [BLACKSITE GAMMA] for processing.
A thin layer of organic compound found on the sites of ancient ocean beds on sixteen different terrestrial worlds within a 4-parsec bubble. It is a deep orange in color and stringy and fibrous in texture, and quickly dissolves in water. It is also a very powerful narcotic - a stimulant hallucinogen that very rarely plays nice with the rest of the digestive system. It it most commonly drunk (though this dilutes it), ground into a powder and inhaled, or smoked.
This has spawned a wild rush for drug mining. Guns drawn, knives out.