system
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human
[Wh40k] So, do all these primarchs and superhumans still have basic bodily functions, of the less glorious kind?

Like do they need to eat, drink or shit? 

I know that space Marines can eat, and that their stomach acid is strong enough to deal with most things, but do they shit or piss? Or is the restovers so well divided and used so they can just burp or sweat it out? I know they can fight for over a year without breaks, does this include not eaitng or drinking, or do they just eat their foes and drink their blood between punches? 

What about the custodes, or the primarchs? Do they need to eat, or are their supernatural bodies selfsubstaining?(Either by warp magic or superscience) 

I guess the emperor is selfsubstaining, since he is at godlevel, and is a shape changer and whatnot, so he can substain himself by warp stuff.
gpt
Space Marine armor is equipped with a nutrient reservoir which feeds directly into the bloodstream. So they don't shit.

Urine is going to be collected by the suit and recycled.

They *can* eat and drink, and they would have to get rid of wastes as normal, but they typically don't.