Premise: Mark `` Conan '' Stevens is an Australian actor , writer , stuntman and former professional wrestler . He is best known for his role as Gregor Clegane in the first season of HBO series Game of Thrones . Ser Gregor Clegane , nicknamed The Mountain , is a fictional character in the A Song of Ice and Fire series of fantasy novels by American author George R. R. Martin , and its television adaptation Game of Thrones . Gregor Clegane is portrayed by Conan Stevens in season one , by Ian Whyte in season two , and by Hafþór Júlíus Björnsson in seasons four , five , and six in the HBO television adaptation . A knight is a person granted an honorary title of knighthood by a monarch or other political leader for service to the monarch or country , especially in a military capacity .
Hypothesis: Gregor Clegane is a fictional dog.
Label: CONTRADICTION