Recent Humans claim to be descendants of the Ancient Orions. Although most empires of the Orion Sector scoff at the arrogance at such a presumption, there is enough uncertainty in Humanity's origins to lend credibility to this 'ancient legitimacy'...

The Psilons have always been devoted to the pursuit of knowledge, a devotion that borders on fanaticism. During the Dark Age, in exchange for favor from the Antaran overlords, the Psilons willingly allowed their Antaran geneticists to experiment on and manipulate their bodies to increase their capacity for learning and research. An example:

[T]he Psilons accidentally discovered an ancient Orion research laboratory… and… deciphered the technologies therein. Most important… was a prototype for an Orion version of a Trans-Dimensional Portal [TDP]… Knowing that they themselves did not have… military muscle… the Psilons wisely chose to trade the TDP technology to all the local Orion races (profiting vastly from the exchanges)…     -- [ MoO3 Manual (Page 70) ]

The Psilons of today are the result of centuries of horrific genetic reconstruction: mentally powerful, but their bodies weakened to the point where they must use hover chairs to move and mechanical waldoes to physically manipulate items in their world.

THE 'ICHTHYTOSIAN' SPECIES

The purpose of the Ichthytosian experiment was to breed aggressive front-line soldiers to be used in upcoming conflicts as disposable shock troops. [..] The Ichthytosians were… not at all what the Antarans wanted — they became very creative, peaceful, artistic creatures who sought to develop their own culture rather than fight. This century-long endeavor was [eventually] dismissed as [a] failure… and the newly evolved Ichthytosians were left alone.     -- [ MoO3 Manual (Page 43) ]

The Nommo are a cephalopodic species that once coexisted with the Trilarians. They left after the War of the Depths to found their own empire, based on their more radical and militaristic beliefs. They believe they are descended directly from the "Old One", the god of the first Ichthytosians who brought them wisdom (and who, ironically, was an Antaran scientist who began the first steps of genetic modification to the Icthytosians). This delusion that they are "children of god" has occasionally led to holy wars against those who might deny them their birthright, most notable the Trilarians who still lay claim to what the Nommo consider "their" homeworld...

[The] Trilarians entered Orion space with the same intent that all the younger races once had: expansion of their empires. [..] [Their] homeworld [eventually]… rested within the bounds of the… [Human federation and] challenged the authority of the Humans.     -- [ MoO3 Manual (Page 55; 67-8) ]

The Trilarians are one of the oldest races in the Orion Sector, and are known for being extreme traditionalists. They are a peaceful race, and their society places great emphasis on art, architecture and philosophy. They have changed very little since the War of the Depths and the Second Exile, trying desperately to regain the glories of their past while preparing for the new future that awaits them in the Orion Sector...