From any publisher: DC, Marvel, Image, etc.
The Spectre is frequently viewed as the most powerful character in the known DC universe. He certainly must have the longest list of on-panel feats to back up that claim among 99% of other characters.
But what about that remaining 1 percent?
I know there are characters who present a greater than the Spectre, both in and out of DC. But which of these rare characters also have the on-panel feats to definitely put them above the Spectre in terms of firepower?