'Game of Thrones' season 6 spoilers, cast rumors: Euron Greyjoy, Samwell Tarly's family, possible Bran flashback

Game of ThronesHBO

"Game of Thrones" season 5 is almost at an end and production for season 6 is set to begin. According to a report from "GoT" spoiler site Watchers on the Wall, the latest casting call for season 6 hints at the introduction of several key characters that haven't been seen in the show thus far. 

Perhaps the most interesting casting call is for a middle-aged pirate. 

"He's 'an infamous pirate who has terrorized seas all around the world. Cunning, ruthless, with a touch of madness.' He's a dangerous-looking man. A very good part this season," reads the casting requirements. 

Fans of "A Song of Ice and Fire" immediately recognize this as a character description for Euron Greyjoy, the eldest of Theon Greyjoy's uncles. He commands the pirate ship Silence, crewed by tongueless men, and is one of the few to have sailed to the ruins of Valyria and back. 

The casting call also hunts for a potential priest. According to the IBTimes, this may fill the role of Septon Meribald but it also fits the description for Aeron "Damphair" Greyjoy, Theon's other uncle who was a former pirate and now priest of the Drowned God. 

If Euron and Aeron are indeed going to be in season 6, then it is possible that they will fulfill the roles these characters had in the books. After Balon Greyjoy dies — which has yet to happen in the TV series — the remaining Greyjoys conduct a "kingsmoot" to choose who their next leader will be. 

The casting call also looks for a family of four: a strict, militaristic father, a sweet and adoring mother, a young sister in her 20's, and a masculine brother. The report from IBTimes points out that these descriptions fit the Tarly family, specifically Lord Randyll Tarly, Sam Tarly's father. 

Also noticeable is the hunt for a 12-year-old boy and a 7-year-old boy with brown hair and both need to have Northern accents. This has led to the speculation that season 6 will feature a flashback when Bran was young. If this is true, then Sean Bean and Mark Addy may return briefly as Lord Eddard Stark and King Robert Baratheon, respectively.