Mroz became the first skater to perform a quadruple Lutz in competition on September 16, 2011 during his Free Skating at the Colorado Springs Invitational, a U.S. Figure Skating sanctioned event. He became also the first man to land a quadruple Lutz in ISU competition at the ISU Grand Prix event NHK Trophy in November 2011. Mroz's mother Cindy used to be a synchronized skater. He took ice dancing lessons and tested up to silver. He is one of four brothers.