Plot hole: Zeus reassures the vast audience of deities in Omnipotent City that the God Butcherer won't reach Eternity, an omnipotent being that will grant one wish to the first person ever to reach it. This knowledge is fairly trivial amongst deities. This introduces the obvious absurdity that nobody ever tried to make use of this power to undo Thanos' damage. Also, Zeus just happens to know the bad guy's plan out of the blue.