10 Comic Book Characters Who Broke Batman
3. Joker
It's impossible not to mention the Joker in this list since he's tormented Batman more than anyone. He's killed Jim Gordon's wife, paralysed Batgirl, lopped off Alfred's arm, and murdered thousands. In terms of getting under Batman's skin though, Joker's crowning achievement was murdering the second Robin, Jason Todd.
Todd went to Africa when he learned his long-lost mother was residing in Ethiopia. Little did he realise that their reunion was concocted by the Joker. He battered Todd with a crowbar before locking him in a warehouse with a bomb. Although Batman rushed to the warehouse as quickly as he could, the bomb detonated, killing Jason Todd.
After he buried his partner, Batman swore that he would hunt Joker to the ends of the Earth to exact his vengeance. The Clown Prince of Crime knew he couldn't hide from his nemesis so he outsmarted him in the most Joker way possible; he became the ambassador of Iran. This position granted the Joker diplomatic immunity, meaning that Batman couldn't touch him without risking an international incident with the country.
Batman sees Jason Todd's death as his greatest failure, and while Joker has come close to traumatising the Dark Knight even more, this still stands out as his worst offence.