I'm actually going to say Overmind. He actually had the Stranger on his knees in a contest of power till he got distracted by the Watchers and Stranger recovered and overpowered him.
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..even the outer hells are indifferent matters for they bow only to potent and archaic Nodens.
That was my pick also. Overmind at his true power level was wrecking house on several occasions including the one you mention. IMO he is a level above these other guys (although he has had appearances at diminished power levels).