Shivan

The Shivans are a sentient species who likely originated in an unexplored region of space.

Physiology
Shivans have multiple eyes, some of which seem to have the function of compound eyes, not unlike some varieties of insects. Shivans also have five legs, and can run equally well over a floor or over a ceiling. It has been hypothesized that Shivans may have spent their evolutionary process in a zero-gravity environment. Each Shivan leg ends in a very strong claw, capable of crushing even the sturdiest of known alloys. Parts of their thorax seem to act as compartments, such as ones that might be found on a space suit. It has been suggested that what we have actually seen have been either robots or organic creatures in some sort of exo-skeleton. However, we have, at present, no reason to support either hypothesis.

Their insect-like carapace does not appear original to the creature's physiology, suggesting the Shivans are a cybernetic fusion of biology and technology. The integrated plasma weapon also exhibits properties of an organic-artificial fusion. The weapon may be a kind of focusing device powered by the energy of the being itself, though this point is the subject of heated controversy. These details are cited as evidence that the Shivans could not have evolved as other species had, but that they were likely constructed by another entity.

Identity and motives
Despite what information we've been able to obtain, Shivans still remain, on many levels, an enigma. Their origin and their destination remain unknown. While many have offered up possible explanations as to why the Shivans seem focused on the destruction of all other sentient species, we still do not know why they seem bent on total xenocide.

The Shivans seem to possess some kind of sensitivity to subspace disturbances. While it is unknown why the Shivans returned, it may have been by chance, cycle, or by the detection of subspace travel and/or conflict.