I always thought Dana Dearden/Obsession/Superwoman had good potential to be a long lasting foe, though some of her themes might be too similar to Maxima, and those aspects could be considered problematic in today's culture without some major revisions. Still, I had some sympathies for the character, and I thought ending up in Hell in the Harley Quinn 1st solo series was a little harsh considering her self-sacrifice.
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