Ten super-villains:
- The Shaggy Man (enemy of the Justice League of America)
- The Human Firefly (enemy of Batman)
- The Pied Piper of Pluto (enemy of Ultra the Multi-Alien)
- U-Man (enemy of the Invaders and the Liberty Legion)
- Dr. Jeremiah Clugg (enemy of the Blue Beetle)
- Dr. Fu Manchu (enemy of Sir Denis Nayland Smith)
- Multi-Face (enemy of Supergirl and Wonder Woman)
- Butch Cavendish (enemy of the Lone Ranger)
- Captain Whale (enemy of Nukla)
- Tchernabog (enemy of Byelun, the White God)
I drew these names from Jeff Rovin's Encyclopedia of Super-Villains, so direct your complaints to him if you don't think any of the above qualify as super-villains. Incidentally, if you haven't already, you should definitely check out the Multi-Face link. There are very few things more unintentionally hilarious than Silver Age DC Comics writers trying to sound hip.