If you want to discuss the ethics of meat-eating, point me at the thread. For this thread I’ll just say that there if the Skeksis chose to draw their life energy from cows I would consider that exactly morally equivalent to them drawing it from turnips.
(Though I will concede that the turnips might not see eye to eye with me on this.)
I think you are referring to potatoes.
I never try to see eye to eye with a potato - all on its own it has me outnumbered.
Don’t play if you can’t win.
We’re doing it now.
Stem Cells.
Unless the stem cells are forcibly removed from someone against their will, it’s not really the same thing. Currently, donors of stem cells are both willing and also are not suffering any sort of loss due to the extraction of stem cells.
One key aspect of the classic villain extracting life force trope is that the victim loses something, even if temporarily, and almost always unwillingly.