Conor McGregor and "The Mountain" from Game of Thrones, also known as Hafthór Júlíus Björnsson, sparred a few months ago and it was quite a sight to see. Here's footage in the form of a gif of the two squaring off with each other...
The Mountain half-jokingly had some 'fighting words' for Conor
"He was trying to punch me. I didn’t feel anything.
He believes he won it. He does not know that I was taking it easy on him because he has a fight and I didn’t want to break him before the fight. He’s worked too much, so I didn’t want to break him."
Here's the entire spar-session:
Conor McGregor has his own take on how that went, though:
Who do you believe?