8) KILLER FROST
A scientist at STAR Labs in Metropolis, Caitlin Frost only received powers when her colleague Barry Allen went back in time and created an alternate timeline he dubbed Flashpoint. Initially, her cryokinetic powers came with a completely altered personality, a vicious amoral woman called Killer Frost, and Caitlin worked to suppress her cold abilities. Eventually, she went full evil, then found her mind again, reversing her face/heel turn and helping Flash defeat the evil speedster Savitar, declaring that Killer Frost was gone, but still possessing her metahuman abilities.