Robbie Rotten

Robbie Rotten is the main antagonist of the children's television show, LazyTown. He is determined to make LazyTown quiet and lazy, as it was before the arrival of Sportacus and Stephanie. In fact, Robbie is determined to run Sportacus out of LazyTown outright, as his championing of a healthy lifestyle and physical-exercise goes against Robbie's goals for the future.

Biography
Robbie used to be comfortable with his life, where he ordered everyone to spend their time lazily and do absolutely nothing, as they had not many beneficial activities to do. One day, Stephanie, and later Sportacus, showed up and introduced sports and other useful activities to the entire town. These actions resulted in drastic changes in Lazy Town, prompting Robbie to do anything he could to undo everything that they did.

Robbie devises all sorts of plans to achieve these objectives, typically using some kind of disguise or gadget to inspire the kids of LazyTown to follow his lazy lifestyle or using them to try to get rid of Sportacus. Although he sometimes comes close to succeeding, in the end, like almost all villains in children's television programs, is always defeated by the show's protagonists.

Personality and Traits
Although his villainy is limited due to the show being geared towards a young audience, he is shown to be the most sneaky, nasty, uncaring, impatient, and potentially "evil" of all LazyTown's residents - having his own underground lair equipped with a periscope and various gadgets.

He has a deep hatred for both Sportacus and Stephanie because they support healthy and fit lifestyles, which Robbie is strongly against. Despite being goofy, he also is quite clever, like most criminal masterminds. Robbie would even go as far as taking someone hostage or steal someone's identity to get his way.

Robbie is a master of disguise, frequently employing varied guises to cause mischief and trouble, and he often shows the typically villainous trait of determination to succeed at his cause despite his repeated failings.

Trivia

 * It is rumored that Robbie's Character was inspired by The Grinch. They both live in secret lairs, they wear disguises to fool townspeople, and they both hate noise. They both even have Canine side-kicks to aid them, although Robbie's Robo-Dog appeared in one episode.
 * Despite being the villain, the kids of LazyTown are sometimes nice to him, which probably speculates that Robbie has a softer or at least a good side.
 * One additional trait of how Robbie is the complete opposite of Sportacus is that, while Sportacus lives in a blimp in the sky, Robbie lives in an underground bunker.
 * Robbie appears to be really smart despite wanting to be lazy.
 * Robbie chooses to sleep in a Lay-Z boy recliner chair rather than in a bed.
 * Robbie Rotten often eats Junk food, such as, blue cake richly covered in white frosting. In fact, this is the only food he has ever been seen consuming, but Robbie also has proven to enjoy pizza, cheeseburgers, french fries, salt water taffy, soda pop and ice cream. But despite this, Robbie has never gotten overweight or obese, and remains slim.
 * The most ironic thing about Robbie is that he wants LazyTown to be lazy, but considering he puts so much effort into his evil schemes, he does not appear to be lazy at all.
 * In the episode, "Robbie's Dream Team," Robbie ordered 3 other villains like himself on the phone. He is disappointed to find out that they are not "real villains" and he has to teach them how to catch Sportacus. While they eventually succeed, they let him go out of boredom.
 * During a Reddit AMA (ask me anything) Stefan Karl revealed that Robbie wishes he could be friends with the kids of LazyTown although it will never happen.