Jack Napier, also known as the Joker, is one of the most iconic villains in DC Comics. He is a criminal mastermind with a clown-like appearance, known for his twisted sense of humor and chaotic plans. The Joker is the archenemy of Batman and often challenges him with elaborate schemes that test Batman's intellect and morals. Despite his chaotic nature, the Joker is highly intelligent and manipulative, making him a formidable foe. His unpredictable behavior and complete disregard for human life make him one of Gotham City's most dangerous criminals.