• Agents of retribution
• Arch enemies
• Archenemies, maybe
• Archrivals
• Baddies
• Banes
• Batman and Robin, to Catwoman
• Batman and Robin, to Riddler
• Batman and Superman, to villains
• Bete noir et al.
• Fierce foes
• Formidable opponents
• Formidable rivals
• Holmes and Moriarty, e.g.
• Like Batman and Robin to the Joker
• Luthor and Brainiac, to Superman
• Mortal enemies
• Plan foilers, perhaps
• Ruins
• See men's foes
• Superheroes, to villains
• The Yankees, to the Red Sox
• They can't be beat
• They give comeuppances
• They're unbeatable
• They're unconquerable
• Thorns in one's side
• Tough opponents
• Unbeatable archenemies
• Unbeatable foes
• Unbeatable opponents
• Unbeatable rivals
• Usually unbeatable rivals
• Vengeful foes
• Waterloos
• Agents of retribution
• Arch enemies
• Archenemies, maybe
• Archrivals
• Baddies
• Banes
• Batman and Robin, to Catwoman
• Batman and Robin, to Riddler
• Batman and Superman, to villains
• Bete noir et al.
• Fierce foes
• Formidable opponents
• Formidable rivals
• Holmes and Moriarty, e.g.
• Like Batman and Robin to the Joker
• Luthor and Brainiac, to Superman
• Mortal enemies
• Plan foilers, perhaps
• Ruins
• See men's foes
• Superheroes, to villains
• The Yankees, to the Red Sox
• They can't be beat
• They give comeuppances
• They're unbeatable
• They're unconquerable
• Thorns in one's side
• Tough opponents
• Unbeatable archenemies
• Unbeatable foes
• Unbeatable opponents
• Unbeatable rivals
• Usually unbeatable rivals
• Vengeful foes
• Waterloos