I know the title main antagonist in Marvel and DC Comics is shared by their most evil and impactful villains (Thanos, Red Skull, Doctor Doom, Galactus)/(Darkseid, Lex Luthor, Joker, Sinestro), but is there any way to determine character(s) who could be "Secondary Antagonists" of the verses? Or are they just too expansive to do so?