Atheleni

The Atheleni are a sapient alien race native to an unnamed temperate planet with two suns. They're biologically-related to, but have a strong social enmity with the Mithraneans.

Biology
The Atheleni are a tripedal mammalian race with keen telepathic abilities and communicate mostly by thoughts. Their sleek bodies are covered in fur, which can be silver (in females) or gold (in males) and which tends to become black with age.

The single powerful rear-limb allows them to leap distances of over 30 feet in a single bound. Their forelegs, in contrast, are considerably shorter and used most importantly for defense, as they end in razor-sharp hooves. In addition, the males possess an ivory horn on their foreheads, which is used as their main physical weapon in battles.

Members of this species are considerably shorter in height than the Mithraneans, with whom they have been at war for years. Still, Atheleni females are often regarded as beautiful by Mithranean standards.

Atheleni can't swim, and thus have a natural aversion towards water. Being herbivorous ruminants, they need to spend a lot of time grazing and digesting their food.

Culture and society
Because they lack hands or any other organ suitable for the manipulation of tools, the Atheleni have never developed technology of any kind, and live a mostly nomadic existence in the idyllic fertile prairies of their home planet.

In compensation, their powerful minds have allowed them to dedicate themselves to the pursuit of advanced mathematics and philosophy, as well as music and performing arts. A curious side effect of this is that they have acquired an elevated knowledge of metaphysics without ever acquiring a basic knowledge of regular physics.

Friendly Atheleni males greet each other by touching their horns.

Mental abilities
The telepathic abilities of Atheleni work better if both parties have known each other for some time. They can communicate with friends and relatives over distance, but can only communicate with strangers when in their actual presence.

On rare occasions, a few individual Atheleni may be born without telepathic abilities and thus be forced to communicate by sounds and gestures.

When two or three Atheleni link their minds, they might become strong enough to influence or exert telepathic control over another individual as long as the subject is willing and cooperative (similar to a stronger form of hypnotism).

Linking the minds of more than three individuals has been considered impossible historically, but due to the war with the Mithraneans, some Atheleni have developed the means to do so, resulting in a collective mind that could only be formed for a few moments, but whose power was many orders of magnitude greater than each of the individuals combined. With this power, they became able to influence even the uncooperative minds of enemy soldiers, and to essentially erase the victim's minds, rendering them as irremediable mental cripples.

Appearances

 * "Second Dawn", by Arthur C. Clarke (1951)