In what might possibly be the most perfect casting decision in the history of the modern world, Ian McShane will return to HBO to appear in Season 6 of Game of Thrones, reports Entertainment Weekly.

The network remains tight-lipped about his role in the fantasy series, but notes that he has "a relatively small amount of screentime during the season, yet his character is of key importance."

McShane, who most recently appeared in Season 3 of Showtime's Ray Donovan, is well known to American audiences for his instantly memorable portrayal of Al Swearengen on Deadwood, a western drama that lasted three seasons before HBO canceled it without a proper ending (not that we're still salty about it or anything).

Game of Thrones could last longer than you think

Game of Thrones is currently in production (just ask Kit Harington) and McShane's casting raises a few questions:

1. For book readers, who do you think McShane is playing? Who do you want him to play?

2. How is it possible that Game of Thrones went five seasons without Ian McShane?

3. How can we get the Thrones' writers to drop a few Deadwood references this season?

On a scale from 1 to Al Swearengen's favorite curse word, how excited are you by this news?

Game of Thrones returns to HBO in 2016.

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