Karen was a college student who underwent a psychological experiment to unlock the full potential of the human mind. She was exposed to subliminal messages and Green-K radiation, causing her to develope amazing powers. However, Karen soon learned that the treatments didn't give her powers, rather they unlocked her existing abilities. Karen learned was in fact an alternate reality version of American Girl from a timeline where she did not die in the Secret Crisis of the Infinity Hour. She had escaped to this reality when her timeline was erased and lost her powers and her memories, and was given the name Karen Webster by the family that found her. With her memories and powers returned, Karen decided to protect her new world as the superheroine Freedom Girl.
Similar to American Girl, Freedom Girl possessed superhuman strength, flight, and invulnerability.