Set decades after the events of The Last Airbender, The Legend of Korra tells the story of Korra, the Avatar following Aang. Unlike her predecessor who only had to defeat Fire Lord Ozai, Korra has to deal with new antagonists every season, as well as several different stories and a myriad of social issues.
To a lot of Avatar fans, the big bad will always be Ozai. He was the Firelord who wanted to rule the world and who Aang spent three seasons training to defeat. He's also incredibly easy to hate because the series didn't spend much time explaining how he was who he was. The Legend of Korra addresses this slight flaw by humanizing its villains. They have backstories, motivations and personal philosophies, and the best of them all is the Bloodbender Amon.
Amon is the primary antagonist in The Legend of Korra Season 1, and he offers some interesting questions about the world of the show. In the series' new, modernized world, cities are compacted thanks to the nations intermingling, crime seems to be running rampant and tensions between benders and non-benders are rising.
Benders vs. non-benders never seemed to be an issue before. In The Last Airbender, most people born without bending take on unique skills that allow them to be as effective as any elemental; however, in the age of industrialization, many non-benders have stopped learning to fight and benders use their abilities for self-gain, like sports and work. It creates a rift among the citizens of Republic City, where non-benders feel the world treats them as second-class citizens.
Amon comes on the scene as an answer to their problems. A man who hides behind a mask, Amon claims to have been chosen by the spirits to fix the balance with his powers to remove someone's bending. He captures benders and strips them of their bending, Korra being one of them. His actions, though drastic and frightening, are hopeful to many people who don't feel equal, and they become equalizers.
In reality, Amon doesn't care about equality for peace's sake. He is actually a Bloodbender from the Northern Water Tribe named Noatak, and he is carrying out his father's revenge. His father, Yakone was a criminal whose bending was taken away by Avatar Aang.
After Yakone fathered two sons, he realizes his children inherited his ability to bloodbend outside of the lunar cycle, so he plans his revenge. He teaches his sons to be bloodbending masters, forcing them to practice on helpless animals and each other, all while drilling into them that the Avatar is corrupt, obsolete and arrogant.
Noatak, while upset with his father, sees the Avatar and the natural ability bestowed to all benders as the source of his pain. If no one could bend, his father may have been a different man, and no one else would have an unfair advantage over another.
Amon as a character raises essential questions about the hierarchy within the Avatar world, and his role as a villain stems from childhood trauma. Amon suffers from Season 1's poor pacing and many subplots, and in the end, he is disregarded as just an extremist Korra takes down. The equalizers and the debate Amon started are dropped the moment he leaves the series, which is unfortunate. All the villains of Korra raise moral questions about their society, but Amon is the one who is the most realistic and compelling.