During an appearance at a recent Heroes & Villains Fan Fest, Stephen Amell addressed if there was any chance that Batman’s most well-known villain The Joker could appear on
Arrow. Amell answered, “Well, I mean, the short answer is yes, of course.
Within the DC Universe, if they are in the DC Universe, if you were to ask if Iron Man could come to Arrow , I would be like, ‘Well, no, probably not.’”
Amell continued, “But of course, The Joker could come to Arrow , Batman could come to Arrow , Superman could show up on The Flash . There’s a whole myriad of options because again DC and WB have a slate of films coming up, and those films happen, and maybe
Arrow’s still around when they’re done. Or maybe there’s a change and people are just like, ‘You know what, let’s invest in something that’s doing well for us.’ So you never know.”