History
Katie Power quit being Energizer during the Regent's rise to power. When either she or her sister, Julie, accidentally used their powers, the Power Pack came back into action.[1] While on the run, the Power Pack was found and recruited into S.H.I.E.L.D..[2]
Paraphernalia
Equipment
Trivia
She appears to be the same age as her Earth-616 counterpart was upon receiving her powers, however that would mean that she wasn't even born yet when Regent rose to power, and did not receive her powers untill Regent had already started hunting down superheroes.