This little easter egg is a reference to a Season 1 episode of Game of Thrones in which the fan-favourite dwarf, Tyrion Lannister, gets imprisoned in a Skycell cell in the Eyrie - a room with three walls and a deadly drop into an abyss instead of the fourth. On a small Skellige isle between Undvik and Kaer Trolde, you can break into an old dungeon guarded by pirates. The cells in the dungeon are just like the three-walled sky cells in Game of Thrones, and walking into one of them you stumble upon the body of a dwarf who looks just like Tyrion - complete with the scar on his face. When Geralt examines the body, he talks about what a good idea 'sky cells' are, and that it's a shame the dwarf didn't know how to 'fly' - a word used often by GoT's Robin, the insufferable prince of the Eyrie who uses the word 'fly' when gleefully talking about throwing people to their deaths from the vertiginous castle.