Fun fact about youre universe?
in earlier periods, clays who conquered other clays would perform ritual cannibalism on them — largely, this was empire-on-empire, or other clays aspiring to be as large as the ones they kill, or very early era clays. usually, this constituted ‘eating’ (not really, rarely did they actually eat them; more so, biting into it) the heart of the conquered. occasionally another part of the body, but those were more so attempts at conquering or threats of some form than a successful campaign. this practice was dying out in the second millennium, and all but dead roughly halfway through the third. one might see references to it in later periods, though.
the heart was chosen not because it was necessary to kill them off, but because it was symbolic of the clay’s continued existence. you cut off the lifeblood, you abolish the empire.