Michaela Dietz was born on November 1, 1982 in South Korea. She is an actress, known for Steven Universe (2013), The Fo-Fo Figgily Show (2014) and Friends with Fins (2014).　　Michaela Dietz is an actress and voice actress whose professional career started in 2005. She is known for playing the role of Riff on Barney and as the voice of Amethyst on the Cartoon Network television series Steven Universe.