The cover theme game works like this: I’ll show you four sets of three covers. Each set of covers has something distinctive in common, whether it be a character, a trait all three characters share, a connection between all three characters, a locale, a trait all three creators share, SOMEthing. And it isn’t something obvious like “They all have prices!” “They all have logos!” “They all feature a man!” “They are all Avengers (who ISN’T?)!” “They’re dead (who HASN’T been killed off?)!” “They’ve all been cloned (who HASN’T been cloned?)!” “They’re all mutants!” (who ISN’T a mutant?) “They’re all orphans!” (who ISN’T an orphan?) “They’re all legacy heroes” (who ISN’T a legacy hero nowadays?)! etc.
In addition, please note that you must have some familiarity with comic book history to correctly guess these themes. You cannot guess the connective theme just by looking at the covers solely, you must have some knowledge beyond the covers. The connections will ONLY have to do with connections in the actual comic books (so no incidental connections like “they share the same last names of Vice Presidents,” etc.).
If you come up with an answer that works outside of what I intended, I’ll give you credit (well, provided I think it fits, of course).
One more thing – if there are floating heads on the cover, ignore them! They don’t mean anything! Same thing with corner boxes!
If you think you know the answer, e-mail me at firstname.lastname@example.org. Don’t answer in the comments. This way, people who check in at different times of the day can still get credit for answering it correctly!
Good luck! And have fun!