In my experience the demon pulls a lot of their civilization's weight. They lead or at least participate in most battles and usually boast the highest kill count of their civilization. It's almost as if the goblins aren't meant to function as proper society without the demon running the show, and the civilization as a whole only exists to serve the demon and the pursuit of their goals. The more thought I put into it, the more familiar it sounds.
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[Laughs in Senate] [Laughs in Darius III's salty tears] [Laughs in Ainur] [Laughs in DAMN BOI HE SWOLE]
This formula doesn't work so well if the demon isn't sufficiently killy or is otherwise prone to catching a case of sudden onset not-being-alive disease. Being the size of a house is a good start and does wonders for intimidation, but if you're made of rock salt or some other fragile material you've got problems. Even exhaling a gas that rots a person's lungs out isn't guaranteed to keep you alive. And any group that can only exist, persist, and excel due to the efforts of one individual is doomed to fall apart they lose their keystone.
Are you sure about that?
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