In her initial paper outlining the analysis of the mysterious alien mineral that would eventually come be to be known as Ouroborite, Professor Heisen noted that when properly refined and controlled the substance could be employed to produce a near limitless source of energy.
She also noted that in it's naturally occurring unrefined state it had a tendency to rip the head of physics, shit down the neck of sanity and thence merrily bugger the corpse of the space/time continuum. All the while laughing hysterically at the very concept of objective reality.
Whilst most scientists feel that it's stretching the term to breaking point, Ouroborite does occur naturally in the galaxy, albeit exclusively on Terror Worlds. That's not a misnomer or overreaction. In an analysis of forty seven different interstellar cultures known to have encountered sources of Ouroborite the terminology employed in the surviiving records exclusively refers to concepts such as terror, hell, punishment, conflict or whatever the nearest cultural equivilent. For example, in the notoriously difficult to comprehend language of the molluscan S'Zzzzrppii culture the worlds bearing Ouroborite are referred to as "Ready-Salted".
The problem with raw Ouroborite is that it seems to resonate in someway with the activity of sentient minds. Psychic energy being one of the types it can be employed to produce under correct conditions. And whilst the minerals callous disregard for the workings of reality is a positive boon when it's controlled to run a star drive, when simply left to act upon the subconscious emotional projections of unsuspecting landing parties the results, whilst no less spectacular, tend to be rather messier.
Traces of indigenous sentient life has not yet been found on any known Terror World. Xeno-Arrcheologists don't really find this surprising. They point out that, even the worlds didn't have a habit of spontaneously reforming their topography whenever anyone lands, the simple fact is that most cultures evolve nightmares before writing. And it's kinda hard to leave traces of civilization when you're being eaten by screaming id monsters as soon as you come down from the trees.
There is a further theory that, in the reality warping field of an Ourorite rich environment, it's probably the trees that actually did for sinister reasons of their own. However this particular school of thought is not commonly accepted as they seem to have difficulty in convincing anyone to grant them funding to actually test the hypothosis.
It is Ouroborite that powers the galactic civilizations. Advanced peaceful ones power whole worlds and run industries free of pollution. Curious star-faring cultures bend space and send fleets to the furthest reaches of space. Warlike races construct really big bombs and terrible flash shredding weaponry. Blood soaked theocracies call down dark gods and thaumaturgists bend reality to their whims in their quest for knowledge. It's almost unheard of for any civilisation to reach an level of advancement worth worrying about without access to the stuff. However actually mining it can be tricky to say the least.
You can't just send an army in to conquer a Terror World. The psychic resonance of that many minds invariably causes a chain reaction resulting in the rise of some cyclopean horror and a world populated by twisted amalgams of flesh and metal, bestial mutated monstrosities, shambling piles of rotting flesh, lakes of acidic ooze with a disturbing flesh like consistency or any of a thousand other horrors. And of course to send in troops of sufficient numbers to combat whatever monstrosity you've created will only make things that much worse. The Federated Galactic Navy informally refers to this process as "Going Thulu", and has developed some rather terrifyingly long range planetary bombardment techniques to deal with such problem cases before they figure out space flight.
Sending artificial probes doesn't help as any machine dumb enough to avoid causing a reaction in the first place isn't actually going to be smart enough to find anything. And Ourborite seems to have a fairly similar effect on artificial conciousness' as it does organic ones. as proved in the now infamous Electric Sheep Incident of the Borghast System. Indeed, many artifical races and robotic cultures have been known to construct specialist Dreamer units in order to take full advantage of Ouroborites unique properties.
However one advantage of the tremendous power available through this unique mineral is that you actually need very little of it to run a planet. So it is that small teams can be dispatched to Terror Worlds equipped with a portable refinery and orbital dispatch unit. They can then scout out Ouroborite deposits and secure them. Of course, being rare, highly valuable and by neccesity extremely isolated it's not unusual for several teams from competing cultures, corporations and interests to be be deployed on the same Terror World. And thus they will often come into conflict. Not only in competition for the precious minerals, but for basic survival. After all, it's bad enough being eaten to death in the night by you're own nightmares come to life. But to be eaten to death in the night by the nightmares of a squid faced alien from the 5th System of Berk?
That's just humiliating.