Actor, Basil Karlo was in a car accident, after learning about his father's untimely death. Permanently disfigured, Karlo used a facial cream called Renuyu from Roland Daggett. But after becoming addicted to the cream and failing to make good on his half of a deal with Roland Daggett, he was exposed to an overwhelming amount of Renuyu which changed his physiology. He now has the ability to shape shift and take the form of any person he would like.  

Take inspiration from Nolan North or Ron Perlman's interpretation of Clayface.