Every year at Comic Con, Game of Thrones producers used to reveal a slew of new characters that would be appearing in the upcoming season of the HBO series. This year, though, that tradition was put to an end, as the producers didn't reveal any new characters or cast members that will show up in Season 6. Since then, there have been several reports and photos from the Game of Thrones set that have revealed new characters, and today we have a new yet unconfirmed report from Watchers On the Wall, which claims that a character who hasn't been seen since Season 3, is coming back. There may be potential SPOILERS below, so read on at your own risk.

The character in question is Brynden Tully, a.k.a. The Blackfish, played by British actor Clive Russell. Blackfish was last seen sneaking out of the infamous Red Wedding at the end of Season 3, and the character has long been thought to be alive, even though we haven't seen him over the past few years. Brynden Tully is the uncle of Catelyn Stark (Michelle Fairley), one of the many who lost their lives during the infamous Red Wedding, along with her son Robb Stark (Richard Madden) and his new bride Talisa (Oona Chaplin).

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This report claims that sources spotted Clive Russell filming scenes in Corbet, Northern Ireland, filming scenes that reportedly involve a massive siege at a Riverlands castle controlled by House Tully, with Brynden Tully defending this building from attackers. This report also claims that Nikolaj Coster-Waldau (Jamie Lannister) and Jerome Flynn (Bronn) were also spotted on the set. There was a report from September that claimed Jamie and Bronn would be travelling to the Riverlands, which has now apparently been confirmed.

While the show has largely caught up to George R.R. Martin's A Song of Fire and Ice novels, it seems these scenes will be based on parts of the author's fourth book, A Feast For Crows, which covers the siege of Riverrun and Brynden Tully's role in that battle. There is another character who has been missing since The Red Wedding, Catelyn's younger brother Edmure (Tobias Menzies), who has been held hostage off screen. The actor has been busy lately with his hit Starz series Outlander, so it isn't known if he will return.

While Clive Russell's return has not been confirmed yet, other Season 6 cast members include Ian McShane in an unspecified role, Pilou Asbæk, who has been rumored to be playing Euron Greyjoy, the uncle of Alfie Allen's Theon Greyjoy and Max von Sydow as the Three-Eyed Raven. Richard E. Grant and Essie Davis are portraying members of a theater troupe who are putting on a play about famous figures in Westeros, with James Faulkner, Samantha Spiro and Rebecca Benson signing on to play the father, mother and sister of Samwell Tarly (John Bradley). What do you think about these new casting details for Game of Thrones?