The Mountain returns to Game of Thrones next season, but with a new face. Yes, another brand new-face.

The role of Ser Gregor Clegane — the same knight who beheaded that poor horse in Season 1 -- has been recast for the second time. Icelandic actor Hafthor Julius Bjornsson announced on Twitter that he's joining HBO's hit fantasy drama as the Mountain, making him the third actor to play the character. He follows in the footsteps of Conan Stevens (Season 1, pictured above) and Ian Whyte (Season 2). The Mountain didn't appear in the third season, but he'll likely have a major part to play in Season 4, depending on how closely the series follows George R.R. Martin's novels.

Bjornsson as Gregor Clegane marks the second major casting change to Game of Thrones in recent weeks. It was revealed in August that Ed Skrein will not return to the series as the mercenary Daario Naharis. Instead, Treme actor Michiel Huisman will occupy that role.

Here's Bjornsson's tweet announcing the news:

For all my fans! I am happy to tell you that I will be THE MOUNTAIN In season 4 In Game Of Thrones :)

— Hafþór J Björnsson (@ThorBjornsson_) September 3, 2013

[Source: Zap2It]