The Obsession With Clowns:
The Joker made his debut in Batman #1 and has since established himself to be a force to be reckoned with in the world of Batman. Originally, the Joker was a scary, cold-blooded thief who planned elaborate and unstoppable murders. A bit of that element has changed over the years to make the villain more psychotic. Arrow’s own version of a clown villain was Bull’s Eye who made his debut in World’s Finest Comics #24. The Green Arrow villain was softer in character just a guy in a clown suit with a bull’s eye on his back.
Around The World Combat Training:
In the comic Batman: Year One, Bruce Wayne spent several years traveling the world to learn various forms of fighting techniques. The Batman before that was not depicted as such, just a millionaire who dabbled in being an arch vigilante during his after hours. Oliver Queen learned his archery after being stranded on an island. The TV series seems to have taken the Batman route and has Oliver train all around the world for his combat training.