He's the physical embodiment of the apathy most feel about comics in general. He's literally the most destructive force capes have ever known: bored readers. He can't "win" in the normal sense, because in his own way, he's been victorious for god knows how long. Like>>98778311
said, if he wants he can end any hero in an instant, but chooses not to bother because he finds it so beneath him, he'd rather let his Gentry monsters mindfuck them to oblivion.
As far as realative powerlevels go, he's the antithesis to the Source/Pressence or the One Above All, since they are essentially the writers, artists and editors that weave the fates of every character. Empty Hand is us, the readers, turning away from comics and narratives, which in truth has almost been the death knell for the entire industry more than once.
Tl;Dr the only way he can possibly be defeated, by anyone, is for you, the comic reader, to just keep reading, just keep the story fueled. Because without us, comic characters are simple lines and colors on a page or screen