I've been warned not to do this, because one of the comic book juggernauts, Marvel, is now owned by Disney, and Disney is super litigious about their intellectual property, going after true offenders and also people who just seem like offenders. Assuming I ignore the warnings, though, how close could I get to Marvel and DC with parody characters without committing copyright or trademark infringement?
Here's my first idea:
This is the Batman parody
Dawn is a city built on crime. Sin runs through her veins. Only one hero dares prowl these dark streets in vain attempt to save her--enter Nightfall and his trusty sidekick Gary the werewolf. Nightfall, a special agent recruited by the hero foundation, comes equipped with a suit that can cancel light for hundreds of feet, creating an illusion capable of blinding and disorienting enemies. He also has an alter ego who is part of the seedy dilapidated underworld, mob member Carson Felts. Moonlighting as one of the city's villains while simultaneously playing the part of her hero, this dark avenger prowls the night.
Frenemies
Monsoon--a beautiful woman who can summon storms with an alluring chant
The Alchemist--a level headed criminal mastermind who can use his alchemical prowess to create deadly chemicals and cast strange spells
Vampire--he's a vampire
Siren--a water-based supervillain who can control water and create and mind control sea life
The Storyteller--an enigmatic villain sorcerer who often works behind the scenes. He believes they're all just characters in a comic book, and he also has an alter ego who runs a comic book shop. He's also obsessed with Nightfall and Carson, perhaps he knows they're one in the same?