(This article is part of a series on realistic and interesting aliens)

Xeltek

The Xeltek look like a mix of a raptor, a scorpion, and your worst nightmares.

They are about as large as a large dog and are heavily armored with a chitin-like plating that covers their entire body. They have six limbs, of which the hind pair have powerful muscles and talons, the front pair has hands, and the mid pair is a strange mix of both that can either provide additional speed and balance when running, or act as a second set of arms when the creature stands only on its hind legs. They also have a tail with a poisonous stinger and are deceptively quick and nimble for how heavily armored they are.

They are a very social species of ambush predators that evolved on the death world Xel, a planet with so much dangerous fauna (and flora) that even the most dangerous dinosaurs on earth would be dead within minutes if they were to be transported to Xel. The Xeltek were already among the most successful predators on the planet before they gained sapience, and became the undisputed apex predators once their brains were large enough to develop and execute more effective ambush tactics to take down even the most dangerous animals on Xel.

They are capable of burrowing underground and can dig elaborate tunnel systems even through hard rock. They live in large communal societies, like ants do, but without a queen. They have short life spans (2 years) but reproduce at an extremely rapid rate (a single female lays dozen of eggs and it takes about 3 months to go from an egg to a mature adult Xeltek.

Most unusually, they possess a sort of telepathic sense. They can detect brainwaves of other creatures in the area, with enough accuracy to understand their surface emotions (they can quite literally sense your fear). They can even sense the presence of other creatures through walls, though not with enough detail to understand what they are thinking. When other Xeltek are close by, this sense is accurate enough that they can exchange memories and experience with each other, including procedural knowledge.

Many other species on Xel also possess this telepathic sense, but none as strongly as the Xeltek. As the Xeltek evolved sapience, their telepathic sense improved as well due to its usefulness for coordination.

For this reason, Xeltek growth is remarkably efficient, as hatchlings can directly copy the life experience of their elders without the need for teaching. They are effectively a pseudo-hivemind. They do not actually share a single mind, but since the transfer of information among them is so efficient it makes little practical difference.

The Xeltek do have a sense of individuality, but they do not value it. A single individual only lives for a few years, but the knowledge they gain lives on as a perfect copy in any other Xeltek they teach. Consequently, their culture is about ideas and concepts and the tribes that embodied them most strongly, not the individuals in those tribes.

After initial conflict between different tribes, they eventually unified into a single well-coordinated civilization with no internal warfare. They debate ideas with great zeal, but no blood is shed in the process.

Given all of these traits, one would assume that the Xeltek are a horrible blight upon the universe and an immense threat to the safety of all other species. Nothing could be further from the truth.

Despite their horrifying predatorial appearance, the Xeltek are (now) an entirely benevolent race.

When they first achieved spaceflight and encountered other species, they were initially hostile and treated the other species as prey. The Xeltek telepathic sense can detect the brainwaves of most other biological species, but since their brains are built very differently they can not parse the information. Because of this, they assumed the other species to be dumb animals, and therefore prey. However, it did not take them long to realize that while the other species was not telepathic, they did communicate through speech. Upon having this realization, the Xeltek immediately stopped all aggression.

The Xeltek have an instinct that lets them recognize other beings as being of the same species as them. This instinct is based largely around the ability to communicate with them, whether through telepathy or not. Once communication was established, their perception switched from animal-we-can-hunt to a-tribe-of-others-like-us.

They are aware that this is irrational, but they do not care. It is the same kind of instinct that humans have that makes us find baby animals cute. We are intellectually aware that they are not actually the same species, but we still treat them nicely much as we would our own babies, and we get angry when other humans harm baby animals.

Ever since the Xeltek learned that sapient alien species can communicate with them, they have been acting overwhelmingly friendly towards aliens, which usually surprises those aliens a great deal.

Due to their heritage as telepathic ambush predators, they have an overwhelming instinctive urge to seek out novelty. This instinct allowed them to always know the weak spots of their prey animals, what migration routes they would take, and other tactically useful information. Following this instinct, all Xeltek constantly seek to gather useful information that can benefit the tribe.

As a result, their science is surprisingly advanced, with a focus on developing technologies that increase the efficiency of the tribe or that help them gather information. The planets settled by Xeltek are completely black, as they are covered in a highly effective photosynthetic substance. Similarly, they have genetically modified their bodies to be pitch black and light absorbent. They are working on fixing aging, with great results so far, and have increased their natural lifespan from two years to twenty.

Perhaps most surprisingly, they are peerless hackers. They instinctively delight in obtaining new information, and so hacking every system they encounter is something they do for fun. They frequently crack top secret military encryptions of other species, completely without hostile intent, just because the information is there and they like seeking it out.

When talking to other species, they are very friendly, if a bit weird because they are not used to non-telepathic species. They are terrible gossips and will talk about anything and everything at the drop of a hat. Sharing useful information with others is a powerful instinct for them and as a telepathic species they don't much understand the idea of need-to-know.

Consequently, they have a tendency to casually reveal important state secrets to random people because it simply doesn't occur to them that they shouldn't. As the secrets they reveal are often things they found out while hacking, they are an absolute security nightmare for other species, even though they don't mean any harm by it.

As a consequence of their rapid growth speed, communal nature and high technology level, they travel through space in enormous world ships. They frequently visit other species to learn about them and share information. This often causes a panic because most species tend to disbelieve that they are only there for tourism when a moon-sized ship full of scary looking monsters shows up, their 'tourists' number in the billions, and they immediately hack into all communication systems.