Gregor Clegane, nicknamed "The Mountain That Rides" or simply "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". In the books, the character is initially introduced in 1996's "A Game of Thrones". He subsequently appeared in "A Clash of Kings" (1998), "A Storm of Swords" (2000) and in "A Dance with Dragons" (2011).

A notorious knight and retainer to House Lannister, he is well known for his enormous size, prowess in battle, extremely cruel nature, and uncontrollable temper. He is the older brother of Sandor "The Hound" Clegane; who has hated him ever since Gregor gruesomely scarred Sandor by shoving his face into a brazier when they were children. After being mortally wounded in a duel with Oberyn Martell, he is resuscitated by Qyburn via sinister means and becomes member of the Kingsguard and the personal bodyguard of Cersei Lannister.

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