 Equally comfortable at or at , Mounis became the first French captain of Catalans in 2007 and featured in every Super League season for the club between 2006 and 2016, having made his debut in the club's inaugural Super League match against Wigan Warriors in 2006.An established international, Mounis featured for France in the 2008 Rugby League World Cup and the 2013 Rugby League World Cup.In 2016 Mounis was named at loose forward in the Dragons' Team of the Decade.