6) The Trickster
The Trickster is not only one of The Flash’s more famous foes, but he might just be his most obnoxious. Despite that, he’s just too iconic not to include in the series at some point, and with the right approach, he could be a great addition to the show and add a lot of entertainment to Barry’s ever-expanding rogues gallery.
Giovanni Giuseppe, who goes by the stage name James Jesse, is a practical joker and conman who uses a wide array of wacky inventions in his fight against the scarlet speedster, including exploding teddy bears, air-walking shoes and other circus-themed gadgets.
While he’s often been associated with the Rogues, the team of Flash villains led by Captain Cold, he’s fought on the right side of the law as well. He often collects the weapons of incarcerated villains so that they don’t get into the wrong hands. So, in that respect, he could come in handy for Barry at some point in the series, and even take possession of Captain Cold’s freeze ray or something.
The Flash has proven to be a pretty light and fun glimpse at the DC Comics Universe thus far, so introducing a zany, theatrical threat like the Trickster could work rather well.