Tbh Superman is as powerful as he needs to be. The metatexual I mean metrosexual thought Robot is greatest, however, the line all things come from Superman is pretty meta textual itself by inference. So perhaps the cloud Siegel imagined was a man flying in the sky might be the most powerful superman.
Quantum Superman is like Doctor Manhattan, not sure if he's as strong as Thought Robot. We all know how powerful Doctor Manhattan was.
I would say Superman with the Sword of Superman is up there as well.
Goldie Superman Prime 1M created his own universe, and was able to revive the original soul of Lois Lane into a silver version of her. Definitely top 4.
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Dunno. Superman definitely sun-dipped longer in OWAW, but he didn't have that omni-dimensional, "power of story" plot armor further amping him, like he did in JL#25.
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Current Superman is considerably more powerful [feat and story-importance wise] in its entirety compared to the early 2000s, as a baseline. His sundip being greater would go in line with that too, imo. That said, both versions were presented as unstoppable and plowed through everything, so eh.
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