One of the most terrifying characters on Game of Thrones has gone all cuddly for his appearance in Katy Perry's new video.

The Mountain aka Ser Gregor Clegane aka Icelandic strongman Thor Björnsson takes a starring role in the basketball-themed video for 'Swish Swish', playing the captain of the fictional Tigers team.

Perry herself plays the captain of the opposing team, The Sheep, and the video also stars Gaten Matarazzo (Dustin from 'Stranger Things'), Molly Shannon and Jenna Ushkowitz from Glee.

Even Nicki Minaj makes a cameo as a cheerleader at one stage.

Watch the trailer for the full video (which is rumoured to go online tomorrow) below: