2. Killer Frost
Given the name Caitlin Snow, comic fans were expecting a little something extra to the character during the first season of The Flash. Namely, that she would become her villainous alter-ego, Killer Frost. Danielle Panabaker confirmed on
Reddit that it would indeed be happening at some point, and there was a little tease in the season 1 finale. Killer Frost is basically like some sort of really evil version of Elsa: she craves heat, with Firestorm being the only one able to sate her needs; can absorb that heat and transmute it into cold waves; put men under her control with a kiss; and create weapons out of ice. Just don't ask her if she wants to build a snowman. With one big-bad already confirmed for season 2 they may be holding back on Frost a little bit, but with such a huge tease now meaning that the entire audience is clamouring to see more of her, the transformation is certain to be happening at some point this year.