Actor Hafþór Júlíus Björnsson, the man behind the helmet on Game of Thrones, is nicknamed Thor for good reason. His 6-foot-9-inch frame and hulking muscles are perfect for the role of Ser Gregor "The Mountain" Clegane.
After Clegane is poisoned by Oberyn Martell's sword during Season 4's trial by combat, Qyburn saves his life with a series of experiments that transform him into something ... else. Think Frankenstein's monster but way, way scarier.
In the Season 6 finale, Septa Unella caught a glimpse of The Mountain's zombified face when he tortured her. (Thanks a lot, Cersei Lannister.) But until today, fans have never clearly seen what hides inside that armor.
Are you ready? Are you sure? Drumroll, please ...
Björnsson took off his helmet for a behind-the-scenes photo, so that solves one GoT mystery. Here's the next one: What'll happen when Sandor Clegane inevitably faces off against his brother? It'll be a long, long winter until we find out.
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