The Joker is a supervillain appearing in American comic books published by DC Comics. The character was created by Bill Finger, Bob Kane, and Jerry Robinson, and first appeared in the debut issue of the comic book Batman on April 25, 1940.
There are roughly one-sh*t billion tropes so PLEASE look through them before adding one. Otherwise add what you like. ADDITION: PLEASE read through the trope description provided before submitting something. It's not a huge deal but too often people submit characters that don't fit just because they misinterpreted the title...