Well, it's no fun to rule over empty and blasted worlds (not that the Dominion hasn't left behind a few million of those as necessary stepping stones in the Overlord's quest to power).
Not to mention that while routine tasks are fine for machines and AIs, the Overlord has always been firmly of the opinion that the living mind is the best source for original concepts. Admittedly, only one in a trillion minds will ascend from mediocrity to achieve true genius. And only one in a million of those will be suitable in other aspects.
But those rare one in a million trillion are worth the nuisance of maintaining all the rest.
It is from these ranks that the Dominion draws its admirals and generals, it's Flag Officers. For while non-AIs and AIs make up the rank and file, and even the officer corps, for true High Command positions only the best and the most sentient will do.
Of course, such troops must be blooded and tested in battle.
Much has been made of the rank-and-file trooper. However, Special Operations requires a unique touch. The living touch.
Different spec-ops units are encouraged to find their own augmentation packages. Some use mystic warrior training and chi powers. Some delve into forbidden arts of magic, combined with elite war colleges. Some believe in the ultra-tech solution, cyborging themselves until they are more machine than man. Some try multiple approaches, or all at once. It pleases the Overlord for such evolution to be in action.
These are only the provisional cadres. To be accepted into the ranks of the Iron Guards, spec-ops troopers must fight and defeat... each other. No training wars these, only the real thing will serve. On planetary surfaces, in the depths of space, the bottom of oceans and the blasted plains of environments man was never meant to tread, the True Soldiers of the Dominion fight and slaughter each other in every way known to man so that the strong may thrive and the weak will die.
Those rare few that survive this grueling mill and rise to the very top of command are granted the Overlord's boons of unaging, disease-free bodies, personal power on an unparalleled scale, and whatever material resources and/or comforts they desire. For they are Imperial Commanders and Iron Guardsmen, the true rulers of both military and civil units of the empire. Planetary governors, Sphere-Ship captains, army commanders, all those are forged in the crucible of war and hardened in the savage intrigue of strife and politics.
But with great power goes great responsibility. An Imperial Commander carries the Emperor's authority with him, and holds the absolute power of life and death within his designated domain. But similarily does he hold absolute responsibility for all that occurs within it, and thus the progression continues up the chain of command, all the way to the Overlord's Court himself.
However, even with all the drawbacks, power such as this draws inhabitants of the Dominion as moths do to a flame, and by the billions do they enlist to compete and fight for the chance to eventually become Iron Guardsmen and Imperial Commanders.
And once in a very rare while, vacancies within the Imperial Court itself have been drawn from the ranks of the Iron Guardsmen. Our own faithful lieutenant MunchKING is one such, the strongest warrior of warriors that the Iron Guard has ever produced. Likewise for Yeoman. Z-Woman was a freelance, a person of great reputation outside the Imperial borders who on the recommendation of Grand Vizier Locke was given the opoprtunity to prove herself and prove that her already noteworthy history was truth and not myth.
It is this ultimate prize that motivates even the most senior of Imperial Commanders.
And as for the Grand Vizier himself...?
It is whispered that he is no man in truth, merely an avatar of the Overlord himself.
It is whispered that he is the Undying One's finest construct, the servant of uttermost loyalty.
It is whispered that... a near infinity of things are whispered.
But no one knows where he came from, or why, or what powers he personally wields. He has always been there. Always at the Overlord's side. No man or machine within the entire Dominion can remember back to a time when he was not there.
Just as no man, save possibly one, knows the true origins of the Overlord.
