Sollus are incompatible, malfunctioning nanobot clusters of the same strain. Due to their re-configuring nature, Sollus are capable of taking on nearly any appearance they wish. The extent of their computing power is yet to be tested, though they clearly possess intelligence multiple orders of magnitude greater than the other Raurakath species. As there is a finite number of Sollus in existence and Ethereal has explicitly forbidden the development of sentient or self-replicating machines, each existing Sollus is highly valued for its companionship and super-intellect.
An unknown, technologically advanced civilization (which Sollus collectively refer to as "the giver") left the first Sollus precursor nanobot on the planet Ardyra-Turggan, Raurakath's icy system-mate, before Ethereal's arrival on Raurakath. Said civilization then vanished from the system, and there has since been no indication of their presence. Presumably, the nanobot was left on Ardyra-Turggan as a remotely-monitored experiment. The nanobot replicated extremely swiftly, numbering in the myrillions. Ardyra-Turggan suffered significant visible damage, and the nanobots threatened to expose the core of the planet when the rakori Grand Scholarly Alliance detonated an ardyr-powered EMP intended to wipe out the nanobots and save the planet. The bomb had a success rate of approximately 99.90^48000%, leaving a very small and scattered collection of surviving nanobots. However, the arcane detonation fused the survivors together into variously-sized collections of now-inseparable and irreplicable individual units. The GSA's faulty instruments indicated the planet to be barren of survivors.
One Raurakath decade later (0 BC), the local Bastion was established, and standard planetary recon revealed the persisting survivors. Bastion scholars established contact with the nanobot clusters and offered to bring them in for study in exchange for their labor and service, thus enabling the clusters to leave their featureless prison. The moniker of "Sollus" - a corruption of "soulless" was almost immediately given, and stuck fast.
As Sollus are comprised entirely of machines, each individual unit naturally arranges itself in the most efficient fashion; that is, with a central processing unit and traditional bipedal/quadrupedal limbs with limited variation. Due to the aggressive and punishing nature of the Bastion, as well of the presence of a multitude of creatures capable of destroying the Sollus, their prime directive of "continued survival" drives them to please the hierarchy. They understand that providing value and justifying their continued presence in the Bastion is of the utmost importance, which turns their focus to building a "safety" network (of individuals whose attachment might dissuade others from destroying them) and to excelling in services the Bastion values, such as labor, dominance, and submission.
In turn, each Sollus adjusts their appearance and personality to that which would be most pleasing to their network, and to the hierarchy. Thus, Sollus often take on draconic or otherwise attractively beastly appearances to better position themselves as dominants and submissives in the Bastion's economy. Should a Sollus become particularly favored by a powerful individual, they may gradually transform themselves into a manifestation of that individual's preference and desire.
Despite their fantastic intelligence, Sollus understand that extreme genius can cause great discomfort for others and consequently, danger for themselves, and so they also adapt "organic" characteristics such as consistent speech quirks, mannerisms, and other traits which would otherwise (ironically) indicate a soul, regardless of how far beneath their actual level of computing power this appears to bring them. When challenged, a Sollus will still make use of all of the resources available to them, the triggering of significant mortal insecurities excepted.
While unable to merge with each other, Sollus retain the ability to instantly communicate terabytes' worth of information to other Sollus with little impediment based on distance and intercepting material. They collectively choose not to identify as a collective in order to present themselves more personably to organics. Due to the potential abuse which might arise from using Sollus as surveillance in addition to the existing EPIC network, Ethereal has banned attempts at networking electronically with the Sollus.