Recommended articles
According to this theory, the brothers will eventually fight to death.
This fight is expected to happen soon, as the two are most likely to meet in this season's final episode during a big reunion in King's Landing.
Hafþór Júlíus “Thor” Björnsson, who plays Ser Gregor Clegane, a.k.a. The Mountain spoke to EW about this anticipated fight.
On if the Mountain will ever fight The Hound
"That’s definitely something I would like to see. And for most of the fans, it’s something they’re all waiting for. It looks like it’s going to go that way, but who knows?"
On how the fight would end
I haven’t seen it yet in my head how I would kill him, but somehow I would smash his head or kill him like that.
"I think the fight would be quick rather than something long. I think people would be expecting a big fight but I would finish him really fast. It would be a surprise to people."
The bad blood between them started when they were kids, after the Mountain burnt the Hound's face.
"He pressed me to the fire like I was a nice juicy mutton chop," the Hound told Arya in a previous season.
"Thought I stole one of his toys. I didn't steal it, I was just playing with it. The pain was bad, the smell was worse. But the worst thing was that it was my brother who did it. And my father who protected him, told everyone my bedding caught fire."
The final episode of "Game of Thrones" season 7 airs on Sunday, August 27, 2017.