The Walking Dead always needs a good villain. It's had several throughout its run. Here are the six meanest.
Joe (Jeff Kober) was the leader of the Claimers, who caused a lot of trouble for the Grimes Gang in Season 4. He earned his "truly bad dude" stripes by being ready, willing and able to rape Michonne (Danai Gurira) and Carl (Chandler Riggs). Fortunately, he was stopped before he got the chance by Rick (Andrew Lincoln) ripping his throat out with his teeth. Rick's only the hero because the show's about him, you know?
Daryl's (Norman Reedus) big brother gets a relatively low showing because he redeemed himself at the end. Merle (Michael Rooker) first showed up in Season 1 and made no friends by being a racist, drug-addicted hothead. In fact, he was so disliked that he got himself handcuffed to a pipe on a roof and was left for dead. He managed to saw his own hand off, disappeared for a season, then reemerged as the Governor's (more on him later) right-hand man without a right hand. He did some bad stuff in this role, including trying to kill Michonne, but he eventually joined the Grimes Gang and died trying to kill the Governor. He loved his brother, he just wasn't always great at showing it.
Gareth (Andrew J. West), the leader of Terminus, was a true creep. Homie was a cannibal. He ate Bob Stookey's (Lawrence Gillard) leg! He was a little too young to have the same villainous gravitas of the guys higher up on the list, but he was definitely the most inhuman.
Shane (Jon Bernthal) was the most complex character The Walking Dead ever had. He basically took over his best friend Rick's life by shacking up with his wife Lori (Sarah Wayne Callies) and taking care of his son when Rick was presumed dead, only to be usurped as the leader of the group when Rick came back. It's pretty understandable that his bitterness and resentment turned violent, to be honest. He wasn't exactly a good guy, but he didn't become a bad guy for no reason.
2. The Governor
Before Negan (Jeffrey Dean Morgan), the Governor (David Morrissey) was the most formidable foe the Grimes Gang faced. The Governor was a psycho with a fish tank full of zombie heads. As his grip on reality declined, he got more and more violent until he became an absolute merciless madman. Scary dude.
But no one's a bigger baddie than Negan, the show's current antagonist. Negan introduced himself by smashing two beloved characters' heads with a baseball bat, an act that's still having repercussions on the show. His subjects kneel when he walks by. That's the level of fear people have for him. Even worse, he's so handsome and charming that you kind of want to forgive him for the awful things he does.
The Walking Dead returns this fall on AMC.