Firestorm

Ronnie Raymond is Firestorm, a living nuclear reactor with the ability to transmute elements. His powers come from the Firestorm Matrix, an energy source that requires him to bond with another being when he turns into Firestorm. His original partner was the brilliant Professor Martin Stein, who originally discovered the Matrix, although he has had several others including Mikhail Arkadin and Jason Rusch. He is a member of the Justice League of America.