I know I've hit this one before, so I'll be brief, but the difficulty finding stuff in the archives is a problem that a new run-through with a tag might solve.
MJ Young has a world setting entitled "The Valley" which I will not go into great detail because I took what little I knew of it, and ran in a wildly different direction.
The Valley is where the verser arrives. It is a green, pleasant dip in the mountains. A lake, and simple huts by the lake and the stream are surrounded by lush, green and undeveloped grasslands with occasional stands of timber.
The locals, of the name I can't remember for sure right now, are roughly three foot tall avian humanoids with brightly patterned and short feathers. Each individual is in their own pattern so they are easy to tell apart.
The tech level is Stone Age. They fish, they build wooden huts, and tell stories.
They have a remarkable gift for mimicry and for language acquisition. In the space of a few hours, they should be able to converse fairly well in the verser's language. They can mimic exactly with ease.
However, they do have something even more unusual. Some of them develop gifts of telepathy, clairvoyance, and telekinesis. Some even can develop pyrokinesis. Those who become strong in these gifts live in a lodge on the hillside overlooking the village.
The lodge's job is to deflect or destroy metereorites that irregularly drop out of orbit, and sometimes would hit the village without intervention. They are quite successful, but they would be glad for more help.
Outside this protected valley, the land is desolate and ruined. Predators stalk the landscape. Some things survive by growing fast enough that random bombardment can't overcome them. Others have good enough eyesight, and quick enough running speed to try to dodge out of the way of a flaming asteroid chunk. But there are a number of things in the wild which would view a tired human trekking the wastelands as an unprotected food source.
What happened in the distant past is the Avians had developed a strong interplanetary economy with a strongly corporatist tendency. This led to a pair of megacorporations gaining control of the planet and its moon. The Moon was highly developed, and generally nicer to live on. The Planet had more overall wealth.
They struggled by means both fair and foul. There were no governments to restrain them as they were the governments.
The Planet Corp decided to launch a crippling attack on the Moon Corp. Meanwhile, the Moon Corp had launched a cyberwar attack of less power on the Planet Corp. The result was that the Planet Corporations finely calibrated surgical strike (OF Doom) turned into a total massacre that shattered the Moon into thousands of pieces. The planet suffered under guilt, but also physical bombardment as chunks of the Moon devastated the Planet, and destroyed most of the population.
In the midst of this run-up, there were a number of research projects. One of them was the development of psionic powers. As the bombardment hit, the test subjects gathered together, and protected each other, and fled...to The Valley where generations later, their descendants live.
Another test project was underway at the time. Cryogenic freezing was being tested for mass use in a few years. Those nearby the research facility, which included a large number of the Planetary leaders who were visiting that day (trying to pretend everything was normal as they launched a surprise attack with thousands of laser cannons). In grief and in fear, the whole of the research facility, much of the leadership, and anyone else nearby went into the cryochambers underneath Cold City. Five thousand were frozen, and their charge was given over to an AI which over time became a bit paranoid, and infected with guilt for its part in the blowing up the moon. Its calculations had been affected by the Moon Corporations cyberattack, and that had helped mess things up.
Now, it tends to keep people away from the ruined towers that is the only thing left of Cold City above ground.
On the Moon, there too had been research projects. They were developing interstellar drive as a way to 'beat out the competition to new markets'.
Some fled the system, and established a series of colonies elsewhere. Long distance telescope work confirmed that their home was wrecked, and would be wrecked for a very long time as a ring of dangerous orbital debris continued to rain down on the planet for centuries, and would continue for millenia.
These colonists with their five solar systems developed cyborging. They used telekinesis to help them fly. They built advanced fletchette autorifles and starships.
But, the great advantages of cyborging came at an unrecognized cost. Without much in the way of tradition to guide them, they did not realize how aberrant they were acting. A dark door had been opened in their minds.
And so it came to war between one of the planets and another. And this war was harsh and dreadful. And then mocking, skirling laughter could be heard. The door was opened wide. Inside, angry at the pain they had suffered, they found a jeering joy in committing horror upon the enemy.
They built a weapon to not only destroy the enemy, but to do it slowly enough that he had plenty of time to realize his fate. They could have built a nova bomb, and wiped out his system. Instead, they chose a Degenerative Paralysis Field which blanketed the planet, and over twelve hours killed everyone.
And they laughed and danced. One of their greatest 'poem-songs' is from this incident, and listening to it wild trills and thundering bass is enough to make most sentients of any humanoid species extremely nervous for it perfectly captures the joy of insane vengeance.
And then they realized what they were. Horror struck, they turned away, and fled into space, and fell through a door in space-time, and made a life on a new planet, in a new universe. Here, they stood, polite, charming, willing to bend over backwards to avoid giving offense. And the reason was that they feared what they would do if the other species were to back them into a corner. That same mad bloodlust still runs through their veins, still sings its seductive song, and they fear themselves greatly.
Now they call themselves the Sarlai Keet.
There are few things more dangerous than backing a Sarlai Keet into a corner. With the cyberware weapons, strength, and speed they can strike incredibly fast; and with their telekinesis they can attack; and their blood madness gives them more advantages.
The Sarlai Keet are focused on avoiding serious conflict. They tend to act in accord with the moral codes of their guests, and to be very proper, but they can quite easily switch to assasinating someone to avert a war.
They have serious problems in their society, and so they were glad when the Emmissaries came in their thousand foot long glass ships to offer the Sarlai Keet a chance to send some of theirs to the Symbiont Academy run by the Galacticans. One question obsesses the Sarlai Keet even more than restraining their madness, or knowing when to let it out. Will someone forgive them? Are they worthy of being forgiven? Do they even want to be forgiven for their is another path...bwahahahhahahahha...mad, skirling laughter trails away...
The Sarlai Keet have come far, and they tend to live in modest skyscrapers with artificial trees for perches outside their home towers.
Most people think the Sarlai Keet are 1)Really nice OR 2)Complete wimps. Few indeed see the laughter in their eyes.