1. The Joker
The Joker is one of the most solid all around villains of all time. He's creepy, he's diabolical, and he's absolutely insane. He's responsible for the deaths of both Jason Todd (The 2nd Robin) and Jim Gordon's second wife, Sarah Essen. He also paralyzed Barbara Gordon (Batgirl). Batman's life has been constantly traumatized due to the Jokers actions. From a character design standpoint The Joker has some very unique characteristics. His green hair and sinister smile could practically pass as trademarks. The Joker will be forever remembered for his deranged laughter and his insane antics that poked at Batmans sanity. He's one of the darkest and most relentless characters ever created. If the Devil had green hair, I think he'd turn out just like the Joker.2. Venom
There are few characters in comics that could actually give someone nightmares, and Venom is one of them. Venom is probably the most intriguing villain of all time because he's not entirely evil. Venom doesn't believe in killing innocent people, he doesn't believe in senseless violence either. Venom only wants to hurt one person, Spider-man. Venom could have easily killed Mary-Jane on several occasions, but he only wants to kill Peter Parker. Venoms design is perfect in many ways. He's big, he's got killer fangs, and that tongue is fierce. Venom is strong, agile, and fast. He's practically impenetrable. Venom currently has his own series running, and its no surprise. He's not just one of the best villains of all time, he's one of the best characters of all time.3. Bullseye
The Joker has done his best to destroy Batman's life in anyway that he can, but even the smiling insanity that is the Joker couldn't mess up Batman's life the way Bullseye has ruined Matt Murdock's. Bullseye killed both Elektra and Karen Page, the two true loves of Matt Murdocks life. Bullseye has one of the best origins of all villains because hes a former baseball pitcher with the accuracy to hit any target. Bullseye is pretty much the only good thing that came out of that atrocity they tried to call a movie starring Ben Affleck as Dardevil. Colin Farrell was perfect as Bullseye as he showed just how insane and evil Bullseye truly is. I'm a loyalist, so when it comes to Bullseye's costume I'm a much bigger fan of the traditional blue costume with the bullseye around the head, but overall the design is fairly simple. In Bullseye's hands, anything is a weapon. I'll always remember in Kevin Smith's Guardian Devil when Bullseye ripped out his two front teeth and threw them at Daredevil. Classic.Ok, here's the thing, DC villains as a whole are pretty weak characters. This is partly because the heroes of the DC universe are usually overpowering and far too unbeatable. However, I didn't feel right putting four straight Marvel Villains in a top five list. I'm giving the nod at number four to Doomsday solely based on the fact that he killed Superman. If Superman's the most powerful super hero, then Doomsday must be a very powerful villain. Doomsday's design is creepy enough, and he certainly looks powerful. However, it's such a shame that Batman has such a solid villain in the Joker, but Superman only has Doomsday and Lex Luthor.
5. The Green Goblin
Venom may be the best villain to come out of Spidey's web of bad guys but the most over looked is clearly the Green Goblin. The goblin has consistently been a nuisance in Peter Parkers life, but nothing tops when he killed Gwen Stacy in what is known as one of the most memorable deaths of all time. That single death has forever followed Spider-man and will always remain in his head as a reminder of what evil his villains are capable of. The Green Goblin may very well be the most underrated villain of all time, but any villain who is responsible for the most remembered death in comics deserves to be on this list.
Honorable Mentions: Dr. Doom, Magneto, Lex Luthor, The Kingpin, and the Red Skull.