The Uul'ba-Rai, known as the Rai for short, are roughly humanoid silicon-based life-forms. Their physique is far tougher than a human's, or any carbon-based life-form, but they move substantially slower.
Their spoken language resembles snaps, crackles and pops, sounding very similar to electrical discharge. This is mainly because they hold an innate electrical charge, and can in fact generate lightning naturally, whether from their own bodies or from clouds. The discipline required to build up their personal charge to useful levels is a field that most of them work at for decades, with some of the most successful being able to spark storms.
Force sensitivity is incredibly rare among them, with only two beings known to have the gift in their entire recorded history.
The Uul'ba-Rai culture has been known to be very fanatical and much of their history has shown them zealously following a religion devoted to their Force-user prophet. This cult was supported by the underlying caste system. Priests were the highest caste, followed by High-Soldiers or Warriors. Next came Low-Soldiers and Citizens. Below these castes were Slaves. Over the course of the rebellion, most of the Priests and High-Soldiers were killed.
Uul'ba-Rai technology is generally behind the modern galactic curve, although they have achieved some impressive accomplishments. Their force-field technology is particularly groundbreaking, and Rai-based shield tech is used in several advanced Jade Empire military designs.
They also demonstrated the ability to siphon energy from a star and use it as a weapon. The actual apparatus had been kept buried for millennia for use against heretics. It was one-of-a-kind weapon and very difficult to duplicate, capable of destroying a capital starship in a single blow, or rip a chunk miles wide out of a planet's crust.