A thought just occurred to me that seems to poke a pretty huge hole in the fabric of the Marathon setting:
The Pfhor run a slave-trading empire and heavily employ slaves themselves, in a galaxy where competent autonomous robots are apparently fairly common.
That's weird because basically the whole reason for inventing robots is that living beings make for expensive and inefficient laborers, even completely neglecting the wellbeing of the laborers. We didn't switch away from animal labor (which was basically non-sapient slavery) to mechanical labor (motor- and engine- driven transportation and production instead of animals pulling carts and turning mill wheels) out of sympathy for the animals, we did it because we could get more work out of it for less total input of our own labor and resources. It's much faster and cheaper and puts out a lot more horsepower to buy a mass-manufactured motor run off of grid power than it is to breed and raise and feed and otherwise keep alive an actual horse and drive it to walk in circles harnessed to a wheel.
More and more skilled labor is harder and harder to automate and so it continues to pay off to have human beings do that for a while but as we're seeing in the real world as automation technology gets better it's taking over more and more jobs that used to be done by humans. And as you get further and further up the ladder of skill levels the incentive to automate gets more and more because it's not like you can grab any old human meat-bag off any street and force them at gunpoint (ignoring the moral aspect of slavery here) to do those remaining hardest-to-do jobs, you need to keep them highly functional and so mentally and consequently physically healthy and give them lots and lots of training and goddamn getting organic flesh beings to do that remaining work gets expensive quickly even if you don't give a shit about their wellbeing for its own sake, so as soon as you can figure out how to build a machine that can do that work, you sure as hell will start mass manufacturing them and free yourself from your costly dependency on these ugly bags of mostly water.
The Pfhor have hovering drones that are apparently mostly designed to do autonomous repair work on technological systems (according to terminal picts), and can apparently also engage in combat (as we're more familiar with them). That indicates a level of competence in their automatons that would make most labor completely redundant. They apparently lack truly sapient AI like Durandal and Tycho, so some highly intellectual tasks may need intelligent organic beings to do them, so having the S'pht do computer-related tasks makes some sense. Conceivably they might want humans for the same purpose, since some of us in the right conditions are capable of that kind of labor, though I think it strains credulity for the reasons described above to take human slaves en masse for that purpose (even the expense of acquiring the slaves seems excessive compared to how many of them will turn out to be useful enough). But what the hell does a Drinniol do that a Hulk-bot wouldn't do better and cheaper? What use is a Nebulon, or a Nar, or a Nahk back in the day when there were Nahk?
Who needs slaves when you've got robots?
