3. Mr. McMahon
If you watched professional wrestling in the late '90s or early 2000s, you wouldn't have found a bigger villain than Mr. McMahon.
Up until that point, WWE Chairman Vince McMahon had either kept himself behind the scenes or appeared on-screen as a commentator, but when the Mr. McMahon character was created, he became a pivotal part of the Attitude Era as he went out of his way to prevent Stone Cold Steve Austin from becoming WWE Champion - and, by extension, the face of the company.
Austin was the company's most popular star at the time, with huge "Austin" chants breaking out during each episode of Monday Night Raw. The only thing louder than those chants was the chorus of boos that would descend upon the arena whenever Mr. McMahon showed up (or attempted to speak). They weren't the only chants, either, as the crowd often had some choice words for him.
A ruthless, power-hungry, selfish, and downright evil character, Mr. McMahon had notable feuds with The Rock, The Undertaker, Kane, Triple H, and more throughout those Attitude Era years and he was very much the villain that the company needed at the time. He may even be WWE's greatest ever villain, and by being so, he created some of its greatest heroes.
The Mr. McMahon character was a necessary evil and the company thrived because of him.