I wanted to make this joke for years
Mordecai: DUDE, WHAT'S YOUR DEAL!?
Muscle Man: Yeah, what's your beef with the park?
Mysterious Stranger: Beef? I have no "Beef" with the park... my "Beef" is with Mordecai and Rigby!
Rigby: But we don't even know you!
Mysterious Stranger: Perhaps not in my current form... but maybe THIS will jog your memory! *Reveals himself to be a floating head* BWAHAHAHAHAHAHA!!!
Mordecai, Rigby, Fives, Muscle man, Skips, and Pops: *Screams in unison... and later in confusion*
Mysterious Stranger: That's right, I'm the Son of Universally renowned gaming champion Garrett Bobby Ferguson... GARRETT BOBBY FERGUSON JR.!!!
Mordecai: Is this just because we beat your Dad's universe record!?
Garrett Bobby Ferguson Jr.: No, IT'S BECAUSE YOU BLEW HIM UP!!! You think you can just go around exploding people's Dads!?
Rigby: Wait, Garrett Bobby Ferguson wasn't married! How could he have a Son!?
Garrett Bobby Ferguson Jr.: He HAPPENED to like hookers, OKAY!?