To say that Iris and Caitlin Snow/Killer Frost have a complicated history would be an understatement. Actually, perhaps, it would be an overstatement. The truth is actually quite simple. Killer Frost tried to kill Iris, and most of Team Flash during one of her temperamental outbursts, induced by her desire to not have superpowers. Confused? Don’t worry, I am too. What matters, though, is the fact that Iris forgave her, and even tried to help Killer Frost in her own time of need. Talk about selfless! During season 4’s “Girl Night Out” episode, Iris put her own life in danger to stop what would have been a nasty, bloody battle between KF and another villain named Amunet. Later on, Iris also used her quick thinking to help defeat Amunet during a second battle.