Some fluff on what dark eldar like to read in the Dark Eldar path trilogy.
The big archons eat extremely well, even better than any imperial. It's by status like everyone says, the low slaves may be forced to eat other slaves.
I memember this scene in the Path of the Renegade, where they had all types of very exotic meats on their table, all coming from extinct animals. even when it comes to food, they're cruel.
Since they are eldar, they also have superior coocking skills.
I know Craftworld eldar are mostly vegetarian, but not 100%. Dark Eldar enjoy rare meats, any type, any animal.
I'm pretty sure most Kabal members eat pretty good food. Warriors may seem low for most people who aren't familiar with the dark eldar fluff, however they are an elite class, they are the best of all the warriors, only chosen because they are the best. It's a lot harder becoming a warrior than you may think. Individuals like incubi are the super mega elite, very experienced and old fighters. (old in age, not in body)
Elite warriors have elite food.
I'm pretty sure Kabal may have cattle of some sort. Commorragh is extremely big, you've got the lviing quarters, the big fortresses where the Archosn hang out, but you also got training ground and factories, whether weapons, or testtube babies. I'm sure that somewhere there are some facilities specialised in food production.
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