Omecs evolved from a quadrupedal carnivore called Zekbatsin. They became bipedal, but also kept certain physical characteristics of their ancestors, including their teeth and feral instinct. They have purple skin, silver hair and silver irises.
For centuries, Omecs became infamous for the practice of traveling to the other Votanis' worlds to kidnap, enslave and even eat them wholesale, their victims eventually numbering in the millions.
They preferred to use their technological advantage over the other races to reign supremely, but over time the enslaved peoples began to rebel, and finally won their freedom while simultaneously turning the tables on their captors in an uprising that became known as "The War of Six," Afterwards, the Omecs were confined to their home planet, now ruled by the Volge.
Deprived of their usual source of slaves and food, the omecs created the Indogenes as an alternative, but the indogenes ended up escaping and joining the collective of votanis.
The other Votan species both feared the Omec and hated the Volge, so they made no attempt to include them in the exodus fleet of "Arks" in which they fled their star system (in 3,001 BC) before it was destroyed in an interstellar collision, ostensibly dooming both the Omecs and the Volge. Thought to be extinct for five millennia, then, it is no great surprise the inhabitants of Earth, especially the Votanis, were taken aback when, during the Pale Wars, the Volge suddenly appeared on scene (possibly recreated through the terraforming of nanites).
The surprise was transformed to shock when, one decade later, an Omec starship arrived in Earth's orbit. The ship turned out to be one that somehow survived the destruction of the original Omec "Ark" fleet when it was systematically destroyed by Indogene bunglers).