Just days after veteran actor Ian McShane joined the cast of Game of Thrones for Season 6, the hit HBO series has added another highly-respected veteran actor. Entertainment Weekly reports that Max von Sydow has signed on to play the Three-Eyed Raven in Game of Thrones this season. Both Ian McShane and Max von Sydow are not expected to have major roles, but each character is described as "crucial." No details were given for Ian McShane's character.

At the end of Season 4, the Three-Eyed Raven finally appeared before Bran Stark (Isaac Hempstead-Wright), after he reached the Weirwood Tree. The Raven was played by a different actor in the Season 4 finale, but now we'll see Max von Sydow as this mystical tutor to Bran. Last season, Bran and his travelling companion Hodor (Kristian Nairn) did not appear at all, since their story was already caught up to the George R.R. Martin books.

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Now the entire series is caught up to the books, and it isn't clear when George R.R. Martin will be able to finish The Winds of Winter, the sixth book in his A Song of Fire and Ice novel series. We reported in June that the show is casting 14 new characters for Game of Thrones Season 6, while another report from May revealed 12 more characters for a total of 26, so we should be hearing about several new casting additions in the weeks and months that follow. There is very little we can glean from the casting details, though, since the sixth book has not been published and there is very little we know about this season's story thus far.

During the TCA summer press tour last week, HBO president Michael Lombardo said that, as of now, series creators David Benioff and D.B. Weiss plan on ending the fantasy TV series after eight seasons. He also hinted at the possibility of a prequel, after Game of Thrones ultimately comes to an end, but nothing is set in stone at this time. Given the massive popularity of the series, it wouldn't be surprising to see the show continue on past an eighth season, or for a prequel show to be put into development as well.

Max von Sydow will next be seen on the big screen in Star Wars: The Force Awakens, arriving in theaters December 18. The actor has only appeared on two TV shows throughout his illustrious career, The Young Indiana Jones Chronicles and The Tudors. Are you looking forward to seeing Max von Sydow alongside Isaac Hempstead-Wright this season? Let us know what you think, and stay tuned for more casting details from Game of Thrones.