a list of all Bart's enemies saying who they are and what they do.
Sideshow Bob Terwilliger
Sideshow Bob Underdunk Terwilliger
Ever since Bart stopped Bob's attempt to frame Krusty the Clown, Bob has been wanting revenge ever since. He has said he wanted to kill Bart several times before, but never succeeded, because Bart, often with the help of Lisa has always managed to outwit him.
Bob has tried to kill Selma, blow up Springfield unless TV was abolished, Build an expressway through the Simpsons' home, frame Krusty, and hypnotize Bart before, but none of his plans have successfully worked. He has a brother, Cecil, who tried to blow up the Springfield Dam.
Principal Seymour Skinner
Principal Skinner, or "Sucker" as Bart refers to him, isn't really a bad enemy. He has given Bart detention many times, but has also teamed up with him a couple of times. Bart made a weather balloon intimidating Skinner before, and ended up spotting a comet. He also saved Lisa when she stole all the school's answer books, telling Skinner it was him. He's also put a flaming bag outside Skinnner's door and many other pranks, all because he hates school. Skinner was so fed up he even recommended Bart to have behaviour-calming drugs. Skinner has tried many punishments to stop Bart, including putting him in Kindergarden, ballet class, expelling him and giving him over 1,000 days detention but Bart mostly has the upper hand on Skinner.
Jimbo, Dolph, Kearney and Nelson
Dolph and Jimbo
The school bullies whose main hobby is beating up other kids, especially Bart as their target. They often beat him and Milhouse up for their lunch money, anything else they want, revenge, or because they want to. Bart has tried to weasel out of beatings before, but with little or no success, although once he did form an army-style group with the help of Grampa to batter Nelson and his henchmen with water bombs. Nelson is the bully who mainly punches Bart when something is wrong. Bart has never squealed to the teachers about it, but they probably wouldn't do much anyway!
Not much is known about Dr.Demento apart from he hosts a radio show and is one of Bart's mortal enemies.
A kid from Shelbyville who hates Springfield and people who hate Shelbyville, Shelby once stole Springfield's lemon tree and Bart vowed to get it back. He did get it back in the end, with the help of Homer and Flanders' van!
Thanks to LETS for these pictures