The Batman: 10 Ways The Riddler Parallels Batman
7. They Take Action Against Injustice
Just like Batman, The Riddler goes out every night to stalk the people he believes are the center of crime infecting the city.
Both of them believe they are acting on the side of justice, and believe their acts will cement their legacy. In actuality, they are just doing this to make themselves feel better.
The Riddler is just angry because the corrupt played a huge part in making his life miserable. While Batman is just angry because random crime took away his parents.
In many ways, The Riddler just wants an excuse to kill the rich, while Batman wants an excuse to beat up the poor. Their motivations are as personal as they are based in even a warped sense of morality - something Batman realises towards the end.