Emmy Award-winning actor Ian McShane has been cast in a secretive role for Game of Thrones season 6.

HBO has declined to announce McShane’s role in the upcoming season, cultivating further mystery around a season already rife with speculation. The character is rumored to be light on screen time (at least for this year) but will evidently be of “key importance” in coming events.

McShane is best known for his roles on HBO’s Deadwood, the BBC’s Lovejoy, and Pirates of the Caribbean: On Stranger Tides, among many other appearances in television and film. The prolific British actor could fit several roles described in casting notices for Game of Thrones season 6, each offering its own unique impact on the sprawling story.

One strong option is the character of Euron Greyjoy, Theon and Yara’s psychotic seafaring uncle. The character is an “infamous pirate who has terrorized seas all around the world,” who is described as “cunning, ruthless, with a touch of madness.” McShane’s intensity and power could easily suit Euron, whose story carries him across multiple power struggles in Westeros and Essos.

Another possibility is the role of an as-yet-unnamed northern lord described as “a massive bear of a man with a beard and temper to match.” The lord, who appears in two episodes, has a capacity for violence, and must have “a powerful physique who can tower over other cast members.”

Other options include Sam’s intimidating father Randyll Tarly, as well as a “gruff ex-soldier” turned “no-nonsense rural priest” who plays a small but powerful role in George R.R. Martin’s book series. And, of course, many other characters remain mysteriously unspecified — McShane could even be joining Game of Thrones season 6 in a role created for the HBO series.

McShane’s casting is just one of several mysteries sprouting up around the sixth season of HBO’s epic fantasy series. The fate of Jon Snow remains a hotly debated topic; though actor Kit Harington was recently seen in Belfast, HBO president Michael Lombardo said yesterday that “everything I’ve seen, heard, and read” indicates that the bastard Lord Commander is totally dead.

But this turmoil and speculation is really just beginning for Game of Thrones season 6. The series will be extending past Martin’s published work next year, setting the stage for more speculation, shocks, and surprises than ever before.

Game of Thrones season 6 will air in Spring 2016 on HBO.

Who do you think Ian McShane will play on ‘Game of Thrones’ season 6?