Eridani: Philosophical methane-breathing humanoids from a rigid caste-bound militocratic society. They follow Kaush-mukal ("Study of the Inner Self"), a philosophy that states that the individual can find enlightenment through performing their function correctly within their cultural niche. The Vax ("warriors") are the upper class; they run the military and control the government. The Tolude ("gentry") are the lesser families of the Vax and form the middle class. They serve as non-commissioned officers and soldiers, technicians and artisans, doctors and nurses, bureaucrats and civil servants, industrialists, bankers, and merchants. The Mudig ("unclean") are the lower-class, who perform the manual trades. They serve as laborers and servants but also provide technical and support services to the military as mechanics, cooks, surgeons and medical orderlies, combat engineers, and other manual tasks.
The Tolude are the most common Eridani to meet offworld as their function often requires it. Vax only leave their world to go on campaign with the military, work as a mercenary, or perform a warrior pilgrimage. Mudig cannot leave their homeworld unless they are on campaign with the military; those who show great bravery and self-sacrifice are adopted by a childless Tolude family or allowed to marry into the Tolude caste.
("Swordsaint"): Elite ascetic warrior-adepts (Mokaba Datu; "Wisdom Warriors") who train in the use of sacred bladed weapons and firearms in order to achieve enlightenment through Goyoo Mabiki ("Silent Peace"; meditation).
(Buddon Priest): Retired warriors who, after finding Rota Mabiki ("Supreme Peace"; enlightenment), have ascended to becoming teachers and philosophers. Senior priests serve as religious commissars, staff officers, and generals in the Eridani armed forces.