I’ve had the opportunity to have stories in several prose superhero anthologies, and for that I am quite greatful. In that spirit, here is a list of superhero themes that I believe would make great anthologies on their own.
1) Replaced: The hero has been replaced by a successor, or an imposter, or a version of themselves from another universe or the future, etc. Examples are numerous, such as Wonderwoman being replaced by Artemis or Hyppolyta are good examples, or the Ben Reilly Spider-Man, or the Christophe version of Dr. Doom, or the various Bat Man replacements (Azreal, Nightwing, etc.)
2) Exposed: The hero’s secret identity has been outed to the public, or his archnemesis has discovered it, or a loved one has found out. An example could be Daredevil’s public outing in the comics, or Spider-Man by the Green Goblin.
3) Framed: The hero has been framed and sent to prison, or slandered until the public hates them, or sought for a crime he didn’t commit. All of these have happened to Spider-Man, but even Bruce Wayne and Daredevil have been sent to prison before.
4) Possessed: The hero has been taken over by an enemy, or mind controlled by the same. Dr. Doom once took over Daredevil’s body, for example, just as Dr. Octopus once took over Spider-Man’s body.
5) Broken Origins: The hero thinks he knows his own origin, but finds out there is a whole lot more to the story than he thought. Examples would be such as when Spider-Man found out his parent were spies and killed by the Red Skull, or when the whole Elektra epic was inserted into the Daredevil story.
6) Fallen: The hero has become a villain, or the villain has become a hero. This might be happen because of mind control, or insanity, or trauma, or loss. Superman in the Injustic video games, or Iron Man (several times), etc.
7) Reborn: The hero has returned from the dead, in fact (Superman) or metaphorically (Batman). Or, a depowered or retired hero has gotten his powers or sense of purpose back. Maybe even an exiled character has been recalled home.
8) Crisis: The hero’s world is ending or rebooting, and his version of reality is getting destroyed. It could be a simple retcon, or an universal retcon, but the character has to wrap up his business and say his goodbyes.
9) Powerless: The hero’s powers have become unpredictable, or are fading, or lost altogether, or replaced with a different set of powers. Think of Superman Blue/Superman Red, for example. Maybe the hero has simply been made redundant.