5. The Viper vs. The Mountain
HBOThe fight scene between Prince Oberyn (aka The Viper) and Gregor Clegane (aka The Mountain) starts off promisingly enough. On the surface, this is a trial by combat, with Oberyn fighting as Tyrion's champion. But there's a ton of history between these two characters -- Clegane is responsible for the rape and murder of Oberyn's sister, and Oberyn is desperate for vengeance. Honestly, we get everything but a, "My name is Inigo Montoya, you killed my father, prepare to die" from him. The Mountain is like eight times the size of Prince Obeyrn and hopped up on the Westeros version of steroids, but Oberyn is fast and very confident. It's a good fight, with both adversaries landing some serious blows. Then, incredibly, it seems like the Mountain has been mortally wounded. All Oberyn has to do is finish him off. But he can't do it. He needs to hear the Mountain confess what he did to his sister, and his thirst for vengeance prevents him from finishing the job. Because even though the Mountain has been stabbed, he's still a giant beast, and he finds just enough strength left in him to pop Oberyn's head like a grape, in what has to be one of Game of Thrones' most truly horrifying visuals.