In the "Silver Surfer: Judgment Day" graphic novel, on page 58, Mephisto is battling with Galactus and says the following thing:
I am Mephisto! Only ONE has the power to defy me, and next to him you are less than a smoldering cinder in the furnace of the damned!
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To whom is Mephisto referring? There are surely a number of beings in the Marvel universe that are not only able to defy him but have actually done it. Who is Mephisto singling out here?